diff --git a/ShopifySharp/Services/Checkout/CheckoutService.cs b/ShopifySharp/Services/Checkout/CheckoutService.cs
index 584265816..149a6d600 100644
--- a/ShopifySharp/Services/Checkout/CheckoutService.cs
+++ b/ShopifySharp/Services/Checkout/CheckoutService.cs
@@ -90,7 +90,7 @@ public virtual async Task<Checkout> UpdateAsync(string token, Checkout updatedCh
         {
             var req = PrepareRequest($"checkouts/{token}.json");
 
-            var response = await ExecuteRequestAsync<Checkout>(req, HttpMethod.Put, cancellationToken, new JsonContent(new { updatedCheckout }), "checkout");
+            var response = await ExecuteRequestAsync<Checkout>(req, HttpMethod.Put, cancellationToken, new JsonContent(new { checkout = updatedCheckout }), "checkout");
             return response.Result;
         }