diff --git a/pkg/compiler/lib/src/inferrer/builder.dart b/pkg/compiler/lib/src/inferrer/builder.dart
index 1f0b057f289..88751a89267 100644
--- a/pkg/compiler/lib/src/inferrer/builder.dart
+++ b/pkg/compiler/lib/src/inferrer/builder.dart
@@ -2141,7 +2141,7 @@ class KernelTypeGraphBuilder extends ir.Visitor<TypeInformation?>
       Local local = _localsMap.getLocalVariable(exception);
       _state.updateLocal(
           _inferrer, _capturedAndBoxed, local, mask, _dartTypes.dynamicType(),
-          excludeNull: true /* `throw null` produces a NullThrownError */);
+          excludeNull: true /* `throw null` produces a TypeError */);
     }
     final stackTrace = node.stackTrace;
     if (stackTrace != null) {
diff --git a/pkg/compiler/lib/src/inferrer_experimental/builder.dart b/pkg/compiler/lib/src/inferrer_experimental/builder.dart
index 02a512f5fd4..d470ccf00bb 100644
--- a/pkg/compiler/lib/src/inferrer_experimental/builder.dart
+++ b/pkg/compiler/lib/src/inferrer_experimental/builder.dart
@@ -2104,7 +2104,7 @@ class KernelTypeGraphBuilder extends ir.Visitor<TypeInformation?>
       Local local = _localsMap.getLocalVariable(exception);
       _state.updateLocal(
           _inferrer, _capturedAndBoxed, local, mask, _dartTypes.dynamicType(),
-          excludeNull: true /* `throw null` produces a NullThrownError */);
+          excludeNull: true /* `throw null` produces a TypeError */);
     }
     final stackTrace = node.stackTrace;
     if (stackTrace != null) {
diff --git a/sdk/lib/_internal/js_runtime/lib/js_helper.dart b/sdk/lib/_internal/js_runtime/lib/js_helper.dart
index 2f380dca6da..604dd45bc5a 100644
--- a/sdk/lib/_internal/js_runtime/lib/js_helper.dart
+++ b/sdk/lib/_internal/js_runtime/lib/js_helper.dart
@@ -1122,7 +1122,7 @@ String checkString(value) {
 /// object out of the wrapper again.
 @pragma('dart2js:noInline')
 wrapException(ex) {
-  if (ex == null) ex = new NullThrownError();
+  if (ex == null) ex = new TypeError();
   var wrapper = JS('', 'new Error()');
   // [unwrapException] looks for the property 'dartException'.
   JS('void', '#.dartException = #', wrapper, ex);
@@ -1586,8 +1586,8 @@ class ExceptionAndStackTrace {
 /// Some native exceptions are mapped to new Dart instances, others are
 /// returned unmodified.
 Object unwrapException(Object? ex) {
-  // Dart converts `null` to `NullThrownError()`. JavaScript can still throw a
-  // nullish value.
+  // Null safe Dart can't throw null, and it is now a `TypeError` in unsound
+  // code. JavaScript can still throw a nullish value.
   if (ex == null) {
     return NullThrownFromJavaScriptException(ex);
   }