diff --git a/packages/react-debug-tools/src/__tests__/ReactHooksInspectionIntegration-test.js b/packages/react-debug-tools/src/__tests__/ReactHooksInspectionIntegration-test.js
index 0b95cf215abcb..78c7e0ee21b44 100644
--- a/packages/react-debug-tools/src/__tests__/ReactHooksInspectionIntegration-test.js
+++ b/packages/react-debug-tools/src/__tests__/ReactHooksInspectionIntegration-test.js
@@ -26,7 +26,7 @@ describe('ReactHooksInspectionIntegration', () => {
     ReactDebugTools = require('react-debug-tools');
   });
 
-  it('should inspect the current state of useState hooks', () => {
+  it('should inspect the current state of useState hooks', async () => {
     const useState = React.useState;
     function Foo(props) {
       const [state1, setState1] = useState('hello');
@@ -61,7 +61,7 @@ describe('ReactHooksInspectionIntegration', () => {
     const {onMouseDown: setStateA, onMouseUp: setStateB} =
       renderer.root.findByType('div').props;
 
-    act(() => setStateA('Hi'));
+    await act(async () => setStateA('Hi'));
 
     childFiber = renderer.root.findByType(Foo)._currentFiber();
     tree = ReactDebugTools.inspectHooksOfFiber(childFiber);
@@ -83,7 +83,7 @@ describe('ReactHooksInspectionIntegration', () => {
       },
     ]);
 
-    act(() => setStateB('world!'));
+    await act(async () => setStateB('world!'));
 
     childFiber = renderer.root.findByType(Foo)._currentFiber();
     tree = ReactDebugTools.inspectHooksOfFiber(childFiber);
@@ -106,7 +106,7 @@ describe('ReactHooksInspectionIntegration', () => {
     ]);
   });
 
-  it('should inspect the current state of all stateful hooks', () => {
+  it('should inspect the current state of all stateful hooks', async () => {
     const outsideRef = React.createRef();
     function effect() {}
     function Foo(props) {
@@ -129,12 +129,8 @@ describe('ReactHooksInspectionIntegration', () => {
       React.useMemo(() => state1 + state2, [state1]);
 
       function update() {
-        act(() => {
-          setState('A');
-        });
-        act(() => {
-          dispatch({value: 'B'});
-        });
+        setState('A');
+        dispatch({value: 'B'});
         ref.current = 'C';
       }
       const memoizedUpdate = React.useCallback(update, []);
@@ -145,7 +141,7 @@ describe('ReactHooksInspectionIntegration', () => {
       );
     }
     let renderer;
-    act(() => {
+    await act(async () => {
       renderer = ReactTestRenderer.create(<Foo prop="prop" />);
     });
 
@@ -207,7 +203,9 @@ describe('ReactHooksInspectionIntegration', () => {
       },
     ]);
 
-    updateStates();
+    await act(async () => {
+      updateStates();
+    });
 
     childFiber = renderer.root.findByType(Foo)._currentFiber();
     tree = ReactDebugTools.inspectHooksOfFiber(childFiber);
@@ -266,7 +264,7 @@ describe('ReactHooksInspectionIntegration', () => {
     ]);
   });
 
-  it('should inspect the current state of all stateful hooks, including useInsertionEffect', () => {
+  it('should inspect the current state of all stateful hooks, including useInsertionEffect', async () => {
     const useInsertionEffect = React.useInsertionEffect;
     const outsideRef = React.createRef();
     function effect() {}
@@ -290,13 +288,9 @@ describe('ReactHooksInspectionIntegration', () => {
 
       React.useMemo(() => state1 + state2, [state1]);
 
-      function update() {
-        act(() => {
-          setState('A');
-        });
-        act(() => {
-          dispatch({value: 'B'});
-        });
+      async function update() {
+        setState('A');
+        dispatch({value: 'B'});
         ref.current = 'C';
       }
       const memoizedUpdate = React.useCallback(update, []);
@@ -307,7 +301,7 @@ describe('ReactHooksInspectionIntegration', () => {
       );
     }
     let renderer;
-    act(() => {
+    await act(async () => {
       renderer = ReactTestRenderer.create(<Foo prop="prop" />);
     });
 
@@ -376,7 +370,9 @@ describe('ReactHooksInspectionIntegration', () => {
       },
     ]);
 
-    updateStates();
+    await act(async () => {
+      updateStates();
+    });
 
     childFiber = renderer.root.findByType(Foo)._currentFiber();
     tree = ReactDebugTools.inspectHooksOfFiber(childFiber);
@@ -967,7 +963,7 @@ describe('ReactHooksInspectionIntegration', () => {
 
   // This test case is based on an open source bug report:
   // https://github.com/facebookincubator/redux-react-hook/issues/34#issuecomment-466693787
-  it('should properly advance the current hook for useContext', () => {
+  it('should properly advance the current hook for useContext', async () => {
     const MyContext = React.createContext(1);
 
     let incrementCount;
diff --git a/packages/react-dom/src/__tests__/ReactDOMConsoleErrorReporting-test.js b/packages/react-dom/src/__tests__/ReactDOMConsoleErrorReporting-test.js
index 03c4f97c4946a..8764c1907bac7 100644
--- a/packages/react-dom/src/__tests__/ReactDOMConsoleErrorReporting-test.js
+++ b/packages/react-dom/src/__tests__/ReactDOMConsoleErrorReporting-test.js
@@ -17,6 +17,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
   let NoError;
   let container;
   let windowOnError;
+  let waitForThrow;
 
   beforeEach(() => {
     jest.resetModules();
@@ -25,6 +26,9 @@ describe('ReactDOMConsoleErrorReporting', () => {
     ReactDOM = require('react-dom');
     ReactDOMClient = require('react-dom/client');
 
+    const InternalTestUtils = require('internal-test-utils');
+    waitForThrow = InternalTestUtils.waitForThrow;
+
     ErrorBoundary = class extends React.Component {
       state = {error: null};
       static getDerivedStateFromError(error) {
@@ -53,7 +57,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
   });
 
   describe('ReactDOMClient.createRoot', () => {
-    it('logs errors during event handlers', () => {
+    it('logs errors during event handlers', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -68,11 +72,11 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       const root = ReactDOMClient.createRoot(container);
-      act(() => {
+      await act(async () => {
         root.render(<Foo />);
       });
 
-      act(() => {
+      await act(async () => {
         container.firstChild.dispatchEvent(
           new MouseEvent('click', {
             bubbles: true,
@@ -142,7 +146,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         root.render(<NoError />);
       });
       expect(container.textContent).toBe('OK');
@@ -152,7 +156,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs render errors without an error boundary', () => {
+    it('logs render errors without an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -160,11 +164,10 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       const root = ReactDOMClient.createRoot(container);
-      expect(() => {
-        act(() => {
-          root.render(<Foo />);
-        });
-      }).toThrow('Boom');
+      await act(async () => {
+        root.render(<Foo />);
+        await waitForThrow('Boom');
+      });
 
       if (__DEV__) {
         expect(windowOnError.mock.calls).toEqual([
@@ -226,7 +229,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         root.render(<NoError />);
       });
       expect(container.textContent).toBe('OK');
@@ -236,7 +239,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs render errors with an error boundary', () => {
+    it('logs render errors with an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -244,7 +247,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       const root = ReactDOMClient.createRoot(container);
-      act(() => {
+      await act(async () => {
         root.render(
           <ErrorBoundary>
             <Foo />
@@ -312,7 +315,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         root.render(<NoError />);
       });
       expect(container.textContent).toBe('OK');
@@ -322,7 +325,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs layout effect errors without an error boundary', () => {
+    it('logs layout effect errors without an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -333,11 +336,10 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       const root = ReactDOMClient.createRoot(container);
-      expect(() => {
-        act(() => {
-          root.render(<Foo />);
-        });
-      }).toThrow('Boom');
+      await act(async () => {
+        root.render(<Foo />);
+        await waitForThrow('Boom');
+      });
 
       if (__DEV__) {
         expect(windowOnError.mock.calls).toEqual([
@@ -382,7 +384,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         root.render(<NoError />);
       });
       expect(container.textContent).toBe('OK');
@@ -392,7 +394,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs layout effect errors with an error boundary', () => {
+    it('logs layout effect errors with an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -403,7 +405,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       const root = ReactDOMClient.createRoot(container);
-      act(() => {
+      await act(async () => {
         root.render(
           <ErrorBoundary>
             <Foo />
@@ -454,7 +456,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         root.render(<NoError />);
       });
       expect(container.textContent).toBe('OK');
@@ -464,7 +466,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs passive effect errors without an error boundary', () => {
+    it('logs passive effect errors without an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -475,11 +477,10 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       const root = ReactDOMClient.createRoot(container);
-      expect(() => {
-        act(() => {
-          root.render(<Foo />);
-        });
-      }).toThrow('Boom');
+      await act(async () => {
+        root.render(<Foo />);
+        await waitForThrow('Boom');
+      });
 
       if (__DEV__) {
         expect(windowOnError.mock.calls).toEqual([
@@ -524,7 +525,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         root.render(<NoError />);
       });
       expect(container.textContent).toBe('OK');
@@ -534,7 +535,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs passive effect errors with an error boundary', () => {
+    it('logs passive effect errors with an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -545,7 +546,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       const root = ReactDOMClient.createRoot(container);
-      act(() => {
+      await act(async () => {
         root.render(
           <ErrorBoundary>
             <Foo />
@@ -596,7 +597,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         root.render(<NoError />);
       });
       expect(container.textContent).toBe('OK');
@@ -608,7 +609,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
   });
 
   describe('ReactDOM.render', () => {
-    it('logs errors during event handlers', () => {
+    it('logs errors during event handlers', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -622,11 +623,11 @@ describe('ReactDOMConsoleErrorReporting', () => {
         );
       }
 
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<Foo />, container);
       });
 
-      act(() => {
+      await act(async () => {
         container.firstChild.dispatchEvent(
           new MouseEvent('click', {
             bubbles: true,
@@ -697,7 +698,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<NoError />, container);
       });
       expect(container.textContent).toBe('OK');
@@ -709,7 +710,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs render errors without an error boundary', () => {
+    it('logs render errors without an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -717,9 +718,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       expect(() => {
-        act(() => {
-          ReactDOM.render(<Foo />, container);
-        });
+        ReactDOM.render(<Foo />, container);
       }).toThrow('Boom');
 
       if (__DEV__) {
@@ -766,7 +765,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<NoError />, container);
       });
       expect(container.textContent).toBe('OK');
@@ -778,14 +777,14 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs render errors with an error boundary', () => {
+    it('logs render errors with an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
         throw Error('Boom');
       }
 
-      act(() => {
+      await act(async () => {
         ReactDOM.render(
           <ErrorBoundary>
             <Foo />
@@ -838,7 +837,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<NoError />, container);
       });
       expect(container.textContent).toBe('OK');
@@ -850,7 +849,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs layout effect errors without an error boundary', () => {
+    it('logs layout effect errors without an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -861,9 +860,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
 
       expect(() => {
-        act(() => {
-          ReactDOM.render(<Foo />, container);
-        });
+        ReactDOM.render(<Foo />, container);
       }).toThrow('Boom');
 
       if (__DEV__) {
@@ -910,7 +907,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<NoError />, container);
       });
       expect(container.textContent).toBe('OK');
@@ -922,7 +919,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs layout effect errors with an error boundary', () => {
+    it('logs layout effect errors with an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -932,7 +929,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
         return null;
       }
 
-      act(() => {
+      await act(async () => {
         ReactDOM.render(
           <ErrorBoundary>
             <Foo />
@@ -985,7 +982,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<NoError />, container);
       });
       expect(container.textContent).toBe('OK');
@@ -997,7 +994,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs passive effect errors without an error boundary', () => {
+    it('logs passive effect errors without an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -1007,11 +1004,10 @@ describe('ReactDOMConsoleErrorReporting', () => {
         return null;
       }
 
-      expect(() => {
-        act(() => {
-          ReactDOM.render(<Foo />, container);
-        });
-      }).toThrow('Boom');
+      await act(async () => {
+        ReactDOM.render(<Foo />, container);
+        await waitForThrow('Boom');
+      });
 
       if (__DEV__) {
         expect(windowOnError.mock.calls).toEqual([
@@ -1057,7 +1053,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<NoError />, container);
       });
       expect(container.textContent).toBe('OK');
@@ -1069,7 +1065,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       }
     });
 
-    it('logs passive effect errors with an error boundary', () => {
+    it('logs passive effect errors with an error boundary', async () => {
       spyOnDevAndProd(console, 'error');
 
       function Foo() {
@@ -1079,7 +1075,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
         return null;
       }
 
-      act(() => {
+      await act(async () => {
         ReactDOM.render(
           <ErrorBoundary>
             <Foo />
@@ -1132,7 +1128,7 @@ describe('ReactDOMConsoleErrorReporting', () => {
       // Check next render doesn't throw.
       windowOnError.mockReset();
       console.error.mockReset();
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<NoError />, container);
       });
       expect(container.textContent).toBe('OK');
diff --git a/packages/react-dom/src/__tests__/ReactDOMFiberAsync-test.js b/packages/react-dom/src/__tests__/ReactDOMFiberAsync-test.js
index 5fc2b2b9744a0..c89ba90866e04 100644
--- a/packages/react-dom/src/__tests__/ReactDOMFiberAsync-test.js
+++ b/packages/react-dom/src/__tests__/ReactDOMFiberAsync-test.js
@@ -620,7 +620,7 @@ describe('ReactDOMFiberAsync', () => {
     expect(container.textContent).toEqual('ABC');
   });
 
-  it('unmounted roots should never clear newer root content from a container', () => {
+  it('unmounted roots should never clear newer root content from a container', async () => {
     const ref = React.createRef();
 
     function OldApp() {
@@ -643,7 +643,7 @@ describe('ReactDOMFiberAsync', () => {
     }
 
     const oldRoot = ReactDOMClient.createRoot(container);
-    act(() => {
+    await act(async () => {
       oldRoot.render(<OldApp />);
     });
 
diff --git a/packages/react-dom/src/__tests__/ReactDOMNativeEventHeuristic-test.js b/packages/react-dom/src/__tests__/ReactDOMNativeEventHeuristic-test.js
index ead8b54eb519b..fd49b824efd71 100644
--- a/packages/react-dom/src/__tests__/ReactDOMNativeEventHeuristic-test.js
+++ b/packages/react-dom/src/__tests__/ReactDOMNativeEventHeuristic-test.js
@@ -74,7 +74,7 @@ describe('ReactDOMNativeEventHeuristic-test', () => {
     }
 
     const root = ReactDOMClient.createRoot(container);
-    await act(() => {
+    await act(async () => {
       root.render(<Form />);
     });
 
diff --git a/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js b/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
index 24ce917a18d5a..18833b0f64da4 100644
--- a/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
+++ b/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
@@ -509,8 +509,8 @@ describe('ReactDOMServerPartialHydration', () => {
     expect(container.innerHTML).toContain('<span>B</span>');
     expect(ref.current).toBe(null);
 
-    expect(() => {
-      act(() => {
+    await expect(async () => {
+      await act(async () => {
         ReactDOMClient.hydrateRoot(container, <App hasB={false} />, {
           onRecoverableError(error) {
             Scheduler.log(error.message);
@@ -579,7 +579,7 @@ describe('ReactDOMServerPartialHydration', () => {
       expect(ref.current).toBe(null);
 
       shouldSuspend = true;
-      act(() => {
+      await act(async () => {
         ReactDOMClient.hydrateRoot(container, <App hasB={false} />);
       });
 
@@ -635,8 +635,8 @@ describe('ReactDOMServerPartialHydration', () => {
     expect(container.innerHTML).toContain('<span>B</span>');
     expect(ref.current).toBe(null);
 
-    expect(() => {
-      act(() => {
+    await expect(async () => {
+      await act(async () => {
         ReactDOMClient.hydrateRoot(container, <App hasB={false} />, {
           onRecoverableError(error) {
             Scheduler.log(error.message);
@@ -698,7 +698,7 @@ describe('ReactDOMServerPartialHydration', () => {
 
     expect(deleted.length).toBe(0);
 
-    act(() => {
+    await act(async () => {
       root.render(<App deleted={true} />);
     });
 
@@ -743,8 +743,8 @@ describe('ReactDOMServerPartialHydration', () => {
 
     // On the client we try to hydrate.
     suspend = true;
-    expect(() => {
-      act(() => {
+    await expect(async () => {
+      await act(async () => {
         ReactDOM.hydrate(<App />, container);
       });
     }).toErrorDev(
@@ -785,7 +785,7 @@ describe('ReactDOMServerPartialHydration', () => {
     expect(container.textContent).toBe('Hello');
   });
 
-  it('can insert siblings before the dehydrated boundary', () => {
+  it('can insert siblings before the dehydrated boundary', async () => {
     let suspend = false;
     const promise = new Promise(() => {});
     let showSibling;
@@ -829,20 +829,20 @@ describe('ReactDOMServerPartialHydration', () => {
     // hydrating anyway.
     suspend = true;
 
-    act(() => {
+    await act(async () => {
       ReactDOMClient.hydrateRoot(container, <App />);
     });
 
     expect(container.firstChild.firstChild.tagName).not.toBe('DIV');
 
     // In this state, we can still update the siblings.
-    act(() => showSibling());
+    await act(async () => showSibling());
 
     expect(container.firstChild.firstChild.tagName).toBe('DIV');
     expect(container.firstChild.firstChild.textContent).toBe('First');
   });
 
-  it('can delete the dehydrated boundary before it is hydrated', () => {
+  it('can delete the dehydrated boundary before it is hydrated', async () => {
     let suspend = false;
     const promise = new Promise(() => {});
     let hideMiddle;
@@ -885,14 +885,14 @@ describe('ReactDOMServerPartialHydration', () => {
     // On the client we don't have all data yet but we want to start
     // hydrating anyway.
     suspend = true;
-    act(() => {
+    await act(async () => {
       ReactDOMClient.hydrateRoot(container, <App />);
     });
 
     expect(container.firstChild.children[1].textContent).toBe('Middle');
 
     // In this state, we can still delete the boundary.
-    act(() => hideMiddle());
+    await act(async () => hideMiddle());
 
     expect(container.firstChild.children[1].textContent).toBe('After');
   });
@@ -1880,7 +1880,7 @@ describe('ReactDOMServerPartialHydration', () => {
     expect(container.textContent).toBe('AB');
 
     // Add more rows before we've hydrated the first two.
-    act(() => {
+    await act(async () => {
       root.render(<App showMore={true} />);
     });
 
@@ -3414,8 +3414,8 @@ describe('ReactDOMServerPartialHydration', () => {
     document.body.appendChild(container);
     container.innerHTML = finalHTML;
 
-    expect(() => {
-      act(() => {
+    await expect(async () => {
+      await act(async () => {
         ReactDOMClient.hydrateRoot(container, <App isClient={true} />, {
           onRecoverableError(error) {
             Scheduler.log('Log recoverable error: ' + error.message);
@@ -3461,8 +3461,8 @@ describe('ReactDOMServerPartialHydration', () => {
     container.innerHTML = ReactDOMServer.renderToString(
       <DirectTextChild text="good" />,
     );
-    expect(() => {
-      act(() => {
+    await expect(async () => {
+      await act(async () => {
         ReactDOMClient.hydrateRoot(container, <DirectTextChild text="bad" />, {
           onRecoverableError(error) {
             Scheduler.log(error.message);
@@ -3502,8 +3502,8 @@ describe('ReactDOMServerPartialHydration', () => {
     container2.innerHTML = ReactDOMServer.renderToString(
       <TextChildWithSibling text="good" />,
     );
-    expect(() => {
-      act(() => {
+    await expect(async () => {
+      await act(async () => {
         ReactDOMClient.hydrateRoot(
           container2,
           <TextChildWithSibling text="bad" />,
diff --git a/packages/react-dom/src/__tests__/ReactErrorBoundaries-test.internal.js b/packages/react-dom/src/__tests__/ReactErrorBoundaries-test.internal.js
index 93e3a04494e43..f9a2a10e74b7a 100644
--- a/packages/react-dom/src/__tests__/ReactErrorBoundaries-test.internal.js
+++ b/packages/react-dom/src/__tests__/ReactErrorBoundaries-test.internal.js
@@ -1862,9 +1862,9 @@ describe('ReactErrorBoundaries', () => {
     assertLog(['ErrorBoundary componentWillUnmount']);
   });
 
-  it('catches errors in useEffect', () => {
+  it('catches errors in useEffect', async () => {
     const container = document.createElement('div');
-    act(() => {
+    await act(async () => {
       ReactDOM.render(
         <ErrorBoundary>
           <BrokenUseEffect>Initial value</BrokenUseEffect>
diff --git a/packages/react-dom/src/__tests__/ReactUpdates-test.js b/packages/react-dom/src/__tests__/ReactUpdates-test.js
index 5555e1b0746c9..5e39cb88d59c3 100644
--- a/packages/react-dom/src/__tests__/ReactUpdates-test.js
+++ b/packages/react-dom/src/__tests__/ReactUpdates-test.js
@@ -1622,7 +1622,7 @@ describe('ReactUpdates', () => {
 
   // TODO: Replace this branch with @gate pragmas
   if (__DEV__) {
-    it('warns about a deferred infinite update loop with useEffect', () => {
+    it('warns about a deferred infinite update loop with useEffect', async () => {
       function NonTerminating() {
         const [step, setStep] = React.useState(0);
         React.useEffect(() => {
@@ -1646,24 +1646,22 @@ describe('ReactUpdates', () => {
       try {
         const container = document.createElement('div');
         expect(() => {
-          act(() => {
-            ReactDOM.render(<App />, container);
-            while (error === null) {
-              Scheduler.unstable_flushNumberOfYields(1);
-              Scheduler.unstable_clearLog();
-            }
-            expect(error).toContain('Warning: Maximum update depth exceeded.');
-            expect(stack).toContain(' NonTerminating');
-            // rethrow error to prevent going into an infinite loop when act() exits
-            throw error;
-          });
+          ReactDOM.render(<App />, container);
+          while (error === null) {
+            Scheduler.unstable_flushNumberOfYields(1);
+            Scheduler.unstable_clearLog();
+          }
+          expect(error).toContain('Warning: Maximum update depth exceeded.');
+          expect(stack).toContain(' NonTerminating');
+          // rethrow error to prevent going into an infinite loop when act() exits
+          throw error;
         }).toThrow('Maximum update depth exceeded.');
       } finally {
         console.error = originalConsoleError;
       }
     });
 
-    it('can have nested updates if they do not cross the limit', () => {
+    it('can have nested updates if they do not cross the limit', async () => {
       let _setStep;
       const LIMIT = 50;
 
@@ -1680,17 +1678,17 @@ describe('ReactUpdates', () => {
       }
 
       const container = document.createElement('div');
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<Terminating />, container);
       });
       expect(container.textContent).toBe('50');
-      act(() => {
+      await act(async () => {
         _setStep(0);
       });
       expect(container.textContent).toBe('50');
     });
 
-    it('can have many updates inside useEffect without triggering a warning', () => {
+    it('can have many updates inside useEffect without triggering a warning', async () => {
       function Terminating() {
         const [step, setStep] = React.useState(0);
         React.useEffect(() => {
@@ -1703,7 +1701,7 @@ describe('ReactUpdates', () => {
       }
 
       const container = document.createElement('div');
-      act(() => {
+      await act(async () => {
         ReactDOM.render(<Terminating />, container);
       });
 
diff --git a/packages/react-interactions/events/src/dom/create-event-handle/__tests__/useFocusWithin-test.internal.js b/packages/react-interactions/events/src/dom/create-event-handle/__tests__/useFocusWithin-test.internal.js
index f34b335cab687..cb8c4ab76a0dc 100644
--- a/packages/react-interactions/events/src/dom/create-event-handle/__tests__/useFocusWithin-test.internal.js
+++ b/packages/react-interactions/events/src/dom/create-event-handle/__tests__/useFocusWithin-test.internal.js
@@ -298,7 +298,7 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
   });
 
   // @gate www
-  it('should correctly handle focus visibility when typing into an input', () => {
+  it('should correctly handle focus visibility when typing into an input', async () => {
     const onFocusWithinVisibleChange = jest.fn();
     const ref = React.createRef();
     const inputRef = React.createRef();
@@ -312,7 +312,7 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
         </div>
       );
     };
-    act(() => {
+    await act(async () => {
       ReactDOM.render(<Component />, container);
     });
 
@@ -477,7 +477,7 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
     });
 
     // @gate www
-    it('is called after a focused suspended element is hidden', () => {
+    it('is called after a focused suspended element is hidden', async () => {
       const Suspense = React.Suspense;
       let suspend = false;
       let resolve;
@@ -508,7 +508,7 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
 
       const root = ReactDOMClient.createRoot(container2);
 
-      act(() => {
+      await act(async () => {
         root.render(<Component />);
       });
       jest.runAllTimers();
@@ -522,7 +522,7 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
       expect(onAfterBlurWithin).toHaveBeenCalledTimes(0);
 
       suspend = true;
-      act(() => {
+      await act(async () => {
         root.render(<Component />);
       });
       jest.runAllTimers();
@@ -535,7 +535,7 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
     });
 
     // @gate www
-    it('is called after a focused suspended element is hidden then shown', () => {
+    it('is called after a focused suspended element is hidden then shown', async () => {
       const Suspense = React.Suspense;
       let suspend = false;
       let resolve;
@@ -567,7 +567,7 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
 
       const root = ReactDOMClient.createRoot(container2);
 
-      act(() => {
+      await act(async () => {
         root.render(<Component />);
       });
       jest.runAllTimers();
@@ -576,14 +576,14 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
       expect(onAfterBlurWithin).toHaveBeenCalledTimes(0);
 
       suspend = true;
-      act(() => {
+      await act(async () => {
         root.render(<Component />);
       });
       jest.runAllTimers();
       expect(onBeforeBlurWithin).toHaveBeenCalledTimes(0);
       expect(onAfterBlurWithin).toHaveBeenCalledTimes(0);
 
-      act(() => {
+      await act(async () => {
         root.render(<Component />);
       });
       jest.runAllTimers();
@@ -592,7 +592,7 @@ describe.each(table)(`useFocus`, hasPointerEvents => {
 
       buttonRef.current.focus();
       suspend = false;
-      act(() => {
+      await act(async () => {
         root.render(<Component />);
       });
       jest.runAllTimers();
diff --git a/packages/react/src/__tests__/ReactProfiler-test.internal.js b/packages/react/src/__tests__/ReactProfiler-test.internal.js
index ac345c0125337..b20442b9e9da9 100644
--- a/packages/react/src/__tests__/ReactProfiler-test.internal.js
+++ b/packages/react/src/__tests__/ReactProfiler-test.internal.js
@@ -270,7 +270,7 @@ describe(`onRender`, () => {
     jest.mock('scheduler', () => jest.requireActual('scheduler/unstable_mock'));
   });
 
-  it('does not report work done on a sibling', () => {
+  it('does not report work done on a sibling', async () => {
     const callback = jest.fn();
 
     const DoesNotUpdate = React.memo(
@@ -646,7 +646,7 @@ describe(`onRender`, () => {
     expect(updateCall[5]).toBe(43); // commit time
   });
 
-  it('should clear nested-update flag when multiple cascading renders are scheduled', () => {
+  it('should clear nested-update flag when multiple cascading renders are scheduled', async () => {
     loadModules({
       useNoopRenderer: true,
     });
@@ -672,7 +672,7 @@ describe(`onRender`, () => {
 
     const onRender = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler id="root" onRender={onRender}>
           <Component />
@@ -1569,7 +1569,7 @@ describe(`onCommit`, () => {
     expect(call[3]).toBe(1011); // commit start time (before mutations or effects)
   });
 
-  it('should bubble time spent in layout effects to higher profilers', () => {
+  it('should bubble time spent in layout effects to higher profilers', async () => {
     const callback = jest.fn();
 
     const ComponentWithEffects = ({cleanupDuration, duration, setCountRef}) => {
@@ -1590,7 +1590,7 @@ describe(`onCommit`, () => {
     const setCountRef = React.createRef(null);
 
     let renderer = null;
-    act(() => {
+    await act(async () => {
       renderer = ReactTestRenderer.create(
         <React.Profiler id="root-mount" onCommit={callback}>
           <React.Profiler id="a">
@@ -1617,7 +1617,7 @@ describe(`onCommit`, () => {
     expect(call[2]).toBe(1010); // durations
     expect(call[3]).toBe(2); // commit start time (before mutations or effects)
 
-    act(() => setCountRef.current(count => count + 1));
+    await act(async () => setCountRef.current(count => count + 1));
 
     expect(callback).toHaveBeenCalledTimes(2);
 
@@ -1629,7 +1629,7 @@ describe(`onCommit`, () => {
     expect(call[2]).toBe(110); // durations
     expect(call[3]).toBe(1013); // commit start time (before mutations or effects)
 
-    act(() => {
+    await act(async () => {
       renderer.update(
         <React.Profiler id="root-update" onCommit={callback}>
           <React.Profiler id="b">
@@ -1650,7 +1650,7 @@ describe(`onCommit`, () => {
     expect(call[3]).toBe(1124); // commit start time (before mutations or effects)
   });
 
-  it('should properly report time in layout effects even when there are errors', () => {
+  it('should properly report time in layout effects even when there are errors', async () => {
     const callback = jest.fn();
 
     class ErrorBoundary extends React.Component {
@@ -1688,7 +1688,7 @@ describe(`onCommit`, () => {
 
     // Test an error that happens during an effect
 
-    act(() => {
+    await act(async () => {
       ReactTestRenderer.create(
         <React.Profiler id="root" onCommit={callback}>
           <ErrorBoundary
@@ -1736,7 +1736,7 @@ describe(`onCommit`, () => {
     expect(call[3]).toBe(10110111); // commit start time (before mutations or effects)
   });
 
-  it('should properly report time in layout effect cleanup functions even when there are errors', () => {
+  it('should properly report time in layout effect cleanup functions even when there are errors', async () => {
     const callback = jest.fn();
 
     class ErrorBoundary extends React.Component {
@@ -1774,7 +1774,7 @@ describe(`onCommit`, () => {
 
     let renderer = null;
 
-    act(() => {
+    await act(async () => {
       renderer = ReactTestRenderer.create(
         <React.Profiler id="root" onCommit={callback}>
           <ErrorBoundary
@@ -1816,7 +1816,7 @@ describe(`onCommit`, () => {
 
     // Test an error that happens during an cleanup function
 
-    act(() => {
+    await act(async () => {
       renderer.update(
         <React.Profiler id="root" onCommit={callback}>
           <ErrorBoundary
@@ -1901,7 +1901,7 @@ describe(`onPostCommit`, () => {
     Scheduler.unstable_advanceTime(1);
 
     let renderer;
-    act(() => {
+    await act(async () => {
       renderer = ReactTestRenderer.create(
         <React.Profiler id="mount-test" onPostCommit={callback}>
           <ComponentWithEffects />
@@ -1922,7 +1922,7 @@ describe(`onPostCommit`, () => {
 
     Scheduler.unstable_advanceTime(1);
 
-    act(() => {
+    await act(async () => {
       renderer.update(
         <React.Profiler id="update-test" onPostCommit={callback}>
           <ComponentWithEffects />
@@ -1943,7 +1943,7 @@ describe(`onPostCommit`, () => {
 
     Scheduler.unstable_advanceTime(1);
 
-    act(() => {
+    await act(async () => {
       renderer.update(
         <React.Profiler id="unmount-test" onPostCommit={callback} />,
       );
@@ -1965,7 +1965,7 @@ describe(`onPostCommit`, () => {
     expect(call[3]).toBe(12030); // commit start time (before mutations or effects)
   });
 
-  it('should report time spent in passive effects with cascading renders', () => {
+  it('should report time spent in passive effects with cascading renders', async () => {
     const callback = jest.fn();
 
     const ComponentWithEffects = () => {
@@ -1985,7 +1985,7 @@ describe(`onPostCommit`, () => {
 
     Scheduler.unstable_advanceTime(1);
 
-    act(() => {
+    await act(async () => {
       ReactTestRenderer.create(
         <React.Profiler id="mount-test" onPostCommit={callback}>
           <ComponentWithEffects />
@@ -2012,7 +2012,7 @@ describe(`onPostCommit`, () => {
     expect(call[3]).toBe(2011); // commit start time (before mutations or effects)
   });
 
-  it('should bubble time spent in effects to higher profilers', () => {
+  it('should bubble time spent in effects to higher profilers', async () => {
     const callback = jest.fn();
 
     const ComponentWithEffects = ({cleanupDuration, duration, setCountRef}) => {
@@ -2033,7 +2033,7 @@ describe(`onPostCommit`, () => {
     const setCountRef = React.createRef(null);
 
     let renderer = null;
-    act(() => {
+    await act(async () => {
       renderer = ReactTestRenderer.create(
         <React.Profiler id="root-mount" onPostCommit={callback}>
           <React.Profiler id="a">
@@ -2060,7 +2060,7 @@ describe(`onPostCommit`, () => {
     expect(call[2]).toBe(1010); // durations
     expect(call[3]).toBe(2); // commit start time (before mutations or effects)
 
-    act(() => setCountRef.current(count => count + 1));
+    await act(async () => setCountRef.current(count => count + 1));
 
     expect(callback).toHaveBeenCalledTimes(2);
 
@@ -2072,7 +2072,7 @@ describe(`onPostCommit`, () => {
     expect(call[2]).toBe(110); // durations
     expect(call[3]).toBe(1013); // commit start time (before mutations or effects)
 
-    act(() => {
+    await act(async () => {
       renderer.update(
         <React.Profiler id="root-update" onPostCommit={callback}>
           <React.Profiler id="b">
@@ -2093,7 +2093,7 @@ describe(`onPostCommit`, () => {
     expect(call[3]).toBe(1124); // commit start time (before mutations or effects)
   });
 
-  it('should properly report time in passive effects even when there are errors', () => {
+  it('should properly report time in passive effects even when there are errors', async () => {
     const callback = jest.fn();
 
     class ErrorBoundary extends React.Component {
@@ -2131,7 +2131,7 @@ describe(`onPostCommit`, () => {
 
     // Test an error that happens during an effect
 
-    act(() => {
+    await act(async () => {
       ReactTestRenderer.create(
         <React.Profiler id="root" onPostCommit={callback}>
           <ErrorBoundary
@@ -2179,7 +2179,7 @@ describe(`onPostCommit`, () => {
     expect(call[3]).toBe(10110111); // commit start time (before mutations or effects)
   });
 
-  it('should properly report time in passive effect cleanup functions even when there are errors', () => {
+  it('should properly report time in passive effect cleanup functions even when there are errors', async () => {
     const callback = jest.fn();
 
     class ErrorBoundary extends React.Component {
@@ -2218,7 +2218,7 @@ describe(`onPostCommit`, () => {
 
     let renderer = null;
 
-    act(() => {
+    await act(async () => {
       renderer = ReactTestRenderer.create(
         <React.Profiler id="root" onPostCommit={callback}>
           <ErrorBoundary
@@ -2260,7 +2260,7 @@ describe(`onPostCommit`, () => {
 
     // Test an error that happens during an cleanup function
 
-    act(() => {
+    await act(async () => {
       renderer.update(
         <React.Profiler id="root" onPostCommit={callback}>
           <ErrorBoundary
@@ -2365,7 +2365,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled).not.toHaveBeenCalled();
   });
 
-  it('is called when a function component schedules an update during a layout effect', () => {
+  it('is called when a function component schedules an update during a layout effect', async () => {
     function Component() {
       const [didMount, setDidMount] = React.useState(false);
       React.useLayoutEffect(() => {
@@ -2377,7 +2377,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2425,7 +2425,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled.mock.calls[0][0]).toBe('root');
   });
 
-  it('bubbles up and calls all ancestor Profilers', () => {
+  it('bubbles up and calls all ancestor Profilers', async () => {
     function Component() {
       const [didMount, setDidMount] = React.useState(false);
       React.useLayoutEffect(() => {
@@ -2438,7 +2438,7 @@ describe(`onNestedUpdateScheduled`, () => {
     const onNestedUpdateScheduledTwo = jest.fn();
     const onNestedUpdateScheduledThree = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="one"
@@ -2466,7 +2466,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduledThree).not.toHaveBeenCalled();
   });
 
-  it('is not called when an update is scheduled for another doort during a layout effect', () => {
+  it('is not called when an update is scheduled for another doort during a layout effect', async () => {
     const setStateRef = React.createRef(null);
 
     function ComponentRootOne() {
@@ -2486,7 +2486,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.renderToRootWithID(
         <React.Profiler
           id="test"
@@ -2514,7 +2514,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled).not.toHaveBeenCalled();
   });
 
-  it('is not called when a function component schedules an update during a passive effect', () => {
+  it('is not called when a function component schedules an update during a passive effect', async () => {
     function Component() {
       const [didMount, setDidMount] = React.useState(false);
       React.useEffect(() => {
@@ -2526,7 +2526,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2540,7 +2540,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled).not.toHaveBeenCalled();
   });
 
-  it('is not called when a function component schedules an update outside of render', () => {
+  it('is not called when a function component schedules an update outside of render', async () => {
     const updateFnRef = React.createRef(null);
 
     function Component() {
@@ -2552,7 +2552,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2563,14 +2563,14 @@ describe(`onNestedUpdateScheduled`, () => {
     });
     assertLog(['Component:false']);
 
-    act(() => {
+    await act(async () => {
       updateFnRef.current();
     });
     assertLog(['Component:true']);
     expect(onNestedUpdateScheduled).not.toHaveBeenCalled();
   });
 
-  it('it is not called when a component schedules an update during render', () => {
+  it('it is not called when a component schedules an update during render', async () => {
     function Component() {
       const [state, setState] = React.useState(false);
       if (state === false) {
@@ -2582,7 +2582,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2596,7 +2596,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled).not.toHaveBeenCalled();
   });
 
-  it('it is called when a component schedules an update from a ref callback', () => {
+  it('it is called when a component schedules an update from a ref callback', async () => {
     function Component({mountChild}) {
       const [refAttached, setRefAttached] = React.useState(false);
       const [refDetached, setRefDetached] = React.useState(false);
@@ -2613,7 +2613,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2627,7 +2627,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled).toHaveBeenCalledTimes(1);
     expect(onNestedUpdateScheduled.mock.calls[0][0]).toBe('test');
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2642,7 +2642,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled.mock.calls[1][0]).toBe('test');
   });
 
-  it('is called when a class component schedules an update from the componentDidMount lifecycles', () => {
+  it('is called when a class component schedules an update from the componentDidMount lifecycles', async () => {
     class Component extends React.Component {
       state = {
         value: false,
@@ -2659,7 +2659,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2674,7 +2674,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled.mock.calls[0][0]).toBe('test');
   });
 
-  it('is called when a class component schedules an update from the componentDidUpdate lifecycles', () => {
+  it('is called when a class component schedules an update from the componentDidUpdate lifecycles', async () => {
     class Component extends React.Component {
       state = {
         nestedUpdateSheduled: false,
@@ -2699,7 +2699,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2711,7 +2711,7 @@ describe(`onNestedUpdateScheduled`, () => {
     assertLog(['Component:false:false']);
     expect(onNestedUpdateScheduled).not.toHaveBeenCalled();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2726,7 +2726,7 @@ describe(`onNestedUpdateScheduled`, () => {
     expect(onNestedUpdateScheduled.mock.calls[0][0]).toBe('test');
   });
 
-  it('is not called when a class component schedules an update outside of render', () => {
+  it('is not called when a class component schedules an update outside of render', async () => {
     const updateFnRef = React.createRef(null);
 
     class Component extends React.Component {
@@ -2743,7 +2743,7 @@ describe(`onNestedUpdateScheduled`, () => {
 
     const onNestedUpdateScheduled = jest.fn();
 
-    act(() => {
+    await act(async () => {
       ReactNoop.render(
         <React.Profiler
           id="test"
@@ -2754,7 +2754,7 @@ describe(`onNestedUpdateScheduled`, () => {
     });
     assertLog(['Component:false']);
 
-    act(() => {
+    await act(async () => {
       updateFnRef.current();
     });
     assertLog(['Component:true']);
diff --git a/packages/react/src/__tests__/ReactStartTransition-test.js b/packages/react/src/__tests__/ReactStartTransition-test.js
index d02a221afb481..8cab56798de5c 100644
--- a/packages/react/src/__tests__/ReactStartTransition-test.js
+++ b/packages/react/src/__tests__/ReactStartTransition-test.js
@@ -27,7 +27,7 @@ describe('ReactStartTransition', () => {
     useTransition = React.useTransition;
   });
 
-  it('Warns if a suspicious number of fibers are updated inside startTransition', () => {
+  it('Warns if a suspicious number of fibers are updated inside startTransition', async () => {
     const subs = new Set();
     const useUserSpaceSubscription = () => {
       const setState = useState(0)[1];
@@ -47,14 +47,14 @@ describe('ReactStartTransition', () => {
       return null;
     };
 
-    act(() => {
+    await act(async () => {
       ReactTestRenderer.create(<Component level={0} />, {
         unstable_isConcurrent: true,
       });
     });
 
-    expect(() => {
-      act(() => {
+    await expect(async () => {
+      await act(async () => {
         React.startTransition(() => {
           subs.forEach(setState => {
             setState(state => state + 1);
@@ -70,8 +70,8 @@ describe('ReactStartTransition', () => {
       {withoutStack: true},
     );
 
-    expect(() => {
-      act(() => {
+    await expect(async () => {
+      await act(async () => {
         triggerHookTransition(() => {
           subs.forEach(setState => {
             setState(state => state + 1);
diff --git a/packages/react/src/__tests__/ReactStrictMode-test.internal.js b/packages/react/src/__tests__/ReactStrictMode-test.internal.js
index 9661d0f72e35d..b0c65c7e22561 100644
--- a/packages/react/src/__tests__/ReactStrictMode-test.internal.js
+++ b/packages/react/src/__tests__/ReactStrictMode-test.internal.js
@@ -45,8 +45,8 @@ describe('ReactStrictMode', () => {
       return null;
     }
 
-    it('should default to not strict', () => {
-      act(() => {
+    it('should default to not strict', async () => {
+      await act(async () => {
         const container = document.createElement('div');
         const root = ReactDOMClient.createRoot(container);
         root.render(<Component label="A" />);
@@ -60,8 +60,8 @@ describe('ReactStrictMode', () => {
     });
 
     if (__DEV__) {
-      it('should support enabling strict mode via createRoot option', () => {
-        act(() => {
+      it('should support enabling strict mode via createRoot option', async () => {
+        await act(async () => {
           const container = document.createElement('div');
           const root = ReactDOMClient.createRoot(container, {
             unstable_strictMode: true,
@@ -81,8 +81,8 @@ describe('ReactStrictMode', () => {
         ]);
       });
 
-      it('should include legacy + strict effects mode', () => {
-        act(() => {
+      it('should include legacy + strict effects mode', async () => {
+        await act(async () => {
           const container = document.createElement('div');
           const root = ReactDOMClient.createRoot(container);
           root.render(
@@ -104,8 +104,8 @@ describe('ReactStrictMode', () => {
         ]);
       });
 
-      it('should allow level to be increased with nesting', () => {
-        act(() => {
+      it('should allow level to be increased with nesting', async () => {
+        await act(async () => {
           const container = document.createElement('div');
           const root = ReactDOMClient.createRoot(container);
           root.render(
diff --git a/packages/react/src/__tests__/ReactStrictMode-test.js b/packages/react/src/__tests__/ReactStrictMode-test.js
index 61d53a7318056..93ad52fe34fb9 100644
--- a/packages/react/src/__tests__/ReactStrictMode-test.js
+++ b/packages/react/src/__tests__/ReactStrictMode-test.js
@@ -356,7 +356,7 @@ describe('ReactStrictMode', () => {
     const root = ReactDOMClient.createRoot(container);
 
     // Mount
-    await act(() => {
+    await act(async () => {
       root.render(
         <React.StrictMode>
           <Uppercased text="hello" />
@@ -372,7 +372,7 @@ describe('ReactStrictMode', () => {
     log = [];
 
     // Update
-    await act(() => {
+    await act(async () => {
       root.render(
         <React.StrictMode>
           <Uppercased text="goodbye" />
@@ -407,7 +407,7 @@ describe('ReactStrictMode', () => {
     const root = ReactDOMClient.createRoot(container);
 
     // Mount
-    await act(() => {
+    await act(async () => {
       root.render(
         <React.StrictMode>
           <Uppercased text="hello" />
@@ -429,7 +429,7 @@ describe('ReactStrictMode', () => {
     log = [];
 
     // Update
-    await act(() => {
+    await act(async () => {
       root.render(
         <React.StrictMode>
           <Uppercased text="goodbye" />
@@ -463,7 +463,7 @@ describe('ReactStrictMode', () => {
     const container = document.createElement('div');
     const root = ReactDOMClient.createRoot(container);
 
-    await act(() => {
+    await act(async () => {
       root.render(
         <React.StrictMode>
           <App />
@@ -472,7 +472,7 @@ describe('ReactStrictMode', () => {
     });
     expect(container.textContent).toBe('0');
 
-    await act(() => {
+    await act(async () => {
       setCount(() => {
         log.push('Compute count: 1');
         return 1;
@@ -501,7 +501,7 @@ describe('ReactStrictMode', () => {
     const container = document.createElement('div');
     const root = ReactDOMClient.createRoot(container);
 
-    await act(() => {
+    await act(async () => {
       root.render(
         <React.StrictMode>
           <App />
@@ -510,7 +510,7 @@ describe('ReactStrictMode', () => {
     });
     expect(container.textContent).toBe('0');
 
-    await act(() => {
+    await act(async () => {
       dispatch(1);
     });
     expect(container.textContent).toBe('1');