diff --git a/src/transforms/bin.js b/src/transforms/bin.js
index 2687d4184f..b9bd1a5b9e 100644
--- a/src/transforms/bin.js
+++ b/src/transforms/bin.js
@@ -4,31 +4,28 @@ import {valueof, first, second, maybeValue, range, offsetRange} from "../mark.js
 export function bin1(options = {}) {
   let {value, domain, thresholds, cumulative} = maybeValue(options);
   const bin = binof({value, domain, thresholds});
-  return (data, facets) => {
-    let bins = bin(data);
-    if (facets !== undefined) return binfacets(bins, facets, subset1, cumulative);
-    if (cumulative) bins = accumulate(cumulative < 0 ? bins.reverse() : bins);
-    bins = bins.filter(nonempty);
-    return {index: range(bins), data: bins};
-  };
+  return (data, facets) => rebin(bin(data), facets, subset1, cumulative);
 }
 
 export function bin2({x = {}, y = {}, domain, thresholds} = {}) {
   const binX = binof({domain, thresholds, value: first, ...maybeValue(x)});
   const binY = binof({domain, thresholds, value: second, ...maybeValue(y)});
-  return (data, facets) => {
-    let bins = cross(binX(data).filter(nonempty), binY(data).filter(nonempty).map(binset), (x, y) => {
-      const subbin = x.filter(i => y.has(i));
-      subbin.x0 = x.x0;
-      subbin.x1 = x.x1;
-      subbin.y0 = y.x0;
-      subbin.y1 = y.x1;
-      return subbin;
-    });
-    if (facets !== undefined) return binfacets(bins, facets, subset2);
-    bins = bins.filter(nonempty);
-    return {index: range(bins), data: bins};
-  };
+  return (data, facets) => rebin(
+    cross(
+      binX(data).filter(nonempty),
+      binY(data).filter(nonempty).map(binset),
+      (x, y) => {
+        const subbin = x.filter(i => y.has(i));
+        subbin.x0 = x.x0;
+        subbin.x1 = x.x1;
+        subbin.y0 = y.x0;
+        subbin.y1 = y.x1;
+        return subbin;
+      }
+    ),
+    facets,
+    subset2
+  );
 }
 
 function binof({value, domain, thresholds}) {
@@ -41,13 +38,19 @@ function binof({value, domain, thresholds}) {
   };
 }
 
-function binfacets(bins, facets, subset, cumulative) {
+// When faceting, subdivides the given bins according to the facet indexes.
+function rebin(bins, facets, subset, cumulative) {
+  if (facets === undefined) {
+    if (cumulative) bins = accumulate(cumulative < 0 ? bins.reverse() : bins);
+    bins = bins.filter(nonempty);
+    return {index: range(bins), data: bins};
+  }
   const index = [];
   const data = [];
   let k = 0;
   for (const facet of facets.map(subset)) {
     let b = bins.map(facet);
-    b = cumulative ? accumulate(cumulative < 0 ? b.reverse() : b) : b;
+    if (cumulative) b = accumulate(cumulative < 0 ? b.reverse() : b);
     b = b.filter(nonempty);
     index.push(offsetRange(b, k));
     data.push(b);