diff --git a/pkg/compiler/lib/src/commandline_options.dart b/pkg/compiler/lib/src/commandline_options.dart
index da0506a..2bbd9c2 100644
--- a/pkg/compiler/lib/src/commandline_options.dart
+++ b/pkg/compiler/lib/src/commandline_options.dart
@@ -34,6 +34,7 @@
   static const String previewDart2 = '--preview-dart-2';
 
   static const String omitImplicitChecks = '--omit-implicit-checks';
+  static const String omitAsCasts = '--omit-as-casts';
   static const String laxRuntimeTypeToString = '--lax-runtime-type-to-string';
 
   static const String platformBinaries = '--platform-binaries=.+';
diff --git a/pkg/compiler/lib/src/dart2js.dart b/pkg/compiler/lib/src/dart2js.dart
index f261270..9fbf28a 100644
--- a/pkg/compiler/lib/src/dart2js.dart
+++ b/pkg/compiler/lib/src/dart2js.dart
@@ -353,6 +353,7 @@
     new OptionHandler('--strong', ignoreOption),
     new OptionHandler(Flags.previewDart2, ignoreOption),
     new OptionHandler(Flags.omitImplicitChecks, passThrough),
+    new OptionHandler(Flags.omitAsCasts, passThrough),
     new OptionHandler(Flags.laxRuntimeTypeToString, passThrough),
     new OptionHandler(Flags.benchmarkingProduction, passThrough),
 
diff --git a/pkg/compiler/lib/src/deferred_load.dart b/pkg/compiler/lib/src/deferred_load.dart
index 4d631c5..5da90be 100644
--- a/pkg/compiler/lib/src/deferred_load.dart
+++ b/pkg/compiler/lib/src/deferred_load.dart
@@ -359,10 +359,14 @@
             case TypeUseKind.INSTANTIATION:
             case TypeUseKind.NATIVE_INSTANTIATION:
             case TypeUseKind.IS_CHECK:
-            case TypeUseKind.AS_CAST:
             case TypeUseKind.CATCH_TYPE:
               _collectTypeDependencies(type, dependencies);
               break;
+            case TypeUseKind.AS_CAST:
+              if (!compiler.options.omitAsCasts) {
+                _collectTypeDependencies(type, dependencies);
+              }
+              break;
             case TypeUseKind.IMPLICIT_CAST:
               if (compiler.options.implicitDowncastCheckPolicy.isEmitted) {
                 _collectTypeDependencies(type, dependencies);
diff --git a/pkg/compiler/lib/src/enqueue.dart b/pkg/compiler/lib/src/enqueue.dart
index fa58347..3cef111 100644
--- a/pkg/compiler/lib/src/enqueue.dart
+++ b/pkg/compiler/lib/src/enqueue.dart
@@ -367,10 +367,14 @@
             nativeUsage: true, globalDependency: true);
         break;
       case TypeUseKind.IS_CHECK:
-      case TypeUseKind.AS_CAST:
       case TypeUseKind.CATCH_TYPE:
         _registerIsCheck(type);
         break;
+      case TypeUseKind.AS_CAST:
+        if (!_options.omitAsCasts) {
+          _registerIsCheck(type);
+        }
+        break;
       case TypeUseKind.IMPLICIT_CAST:
         if (_options.implicitDowncastCheckPolicy.isEmitted) {
           _registerIsCheck(type);
diff --git a/pkg/compiler/lib/src/js_backend/enqueuer.dart b/pkg/compiler/lib/src/js_backend/enqueuer.dart
index 361a39b..44c9b93 100644
--- a/pkg/compiler/lib/src/js_backend/enqueuer.dart
+++ b/pkg/compiler/lib/src/js_backend/enqueuer.dart
@@ -180,10 +180,14 @@
         _registerInstantiatedType(type, nativeUsage: true);
         break;
       case TypeUseKind.IS_CHECK:
-      case TypeUseKind.AS_CAST:
       case TypeUseKind.CATCH_TYPE:
         _registerIsCheck(type);
         break;
+      case TypeUseKind.AS_CAST:
+        if (!_options.omitAsCasts) {
+          _registerIsCheck(type);
+        }
+        break;
       case TypeUseKind.IMPLICIT_CAST:
         if (_options.implicitDowncastCheckPolicy.isEmitted) {
           _registerIsCheck(type);
diff --git a/pkg/compiler/lib/src/js_backend/impact_transformer.dart b/pkg/compiler/lib/src/js_backend/impact_transformer.dart
index 8876430..282086e 100644
--- a/pkg/compiler/lib/src/js_backend/impact_transformer.dart
+++ b/pkg/compiler/lib/src/js_backend/impact_transformer.dart
@@ -160,8 +160,10 @@
           onIsCheck(type, transformed);
           break;
         case TypeUseKind.AS_CAST:
-          onIsCheck(type, transformed);
-          hasAsCast = true;
+          if (!_options.omitAsCasts) {
+            onIsCheck(type, transformed);
+            hasAsCast = true;
+          }
           break;
         case TypeUseKind.IMPLICIT_CAST:
           if (_options.implicitDowncastCheckPolicy.isEmitted) {
diff --git a/pkg/compiler/lib/src/options.dart b/pkg/compiler/lib/src/options.dart
index 7583e78..9dbf70e 100644
--- a/pkg/compiler/lib/src/options.dart
+++ b/pkg/compiler/lib/src/options.dart
@@ -182,6 +182,9 @@
   /// Whether to omit implicit strong mode checks.
   bool omitImplicitChecks = false;
 
+  /// Whether to omit as casts.
+  bool omitAsCasts = false;
+
   /// Whether to omit class type arguments only needed for `toString` on
   /// `Object.runtimeType`.
   bool laxRuntimeTypeToString = false;
@@ -294,6 +297,7 @@
           platformBinaries ?? _extractUriOption(options, '--platform-binaries=')
       ..sourceMapUri = _extractUriOption(options, '--source-map=')
       ..omitImplicitChecks = _hasOption(options, Flags.omitImplicitChecks)
+      ..omitAsCasts = _hasOption(options, Flags.omitAsCasts)
       ..laxRuntimeTypeToString =
           _hasOption(options, Flags.laxRuntimeTypeToString)
       ..testMode = _hasOption(options, Flags.testMode)
diff --git a/pkg/compiler/lib/src/ssa/builder_kernel.dart b/pkg/compiler/lib/src/ssa/builder_kernel.dart
index f1d01fb..185ea5b 100644
--- a/pkg/compiler/lib/src/ssa/builder_kernel.dart
+++ b/pkg/compiler/lib/src/ssa/builder_kernel.dart
@@ -2066,7 +2066,8 @@
     }
 
     DartType type = _elementMap.getDartType(node.type);
-    if (!node.isTypeError || options.implicitDowncastCheckPolicy.isEmitted) {
+    if ((!node.isTypeError && !options.omitAsCasts) ||
+        options.implicitDowncastCheckPolicy.isEmitted) {
       HInstruction converted = typeBuilder.buildTypeConversion(
           expressionInstruction,
           localsHandler.substInContext(type),