diff --git a/src/renderers/__tests__/ReactUpdates-test.js b/src/renderers/__tests__/ReactUpdates-test.js
index 16812b3aba9dd..ead339ba85587 100644
--- a/src/renderers/__tests__/ReactUpdates-test.js
+++ b/src/renderers/__tests__/ReactUpdates-test.js
@@ -522,10 +522,7 @@ describe('ReactUpdates', () => {
         var portal = null;
         // If we're using Fiber, we use Portals instead to achieve this.
         if (ReactDOMFeatureFlags.useFiber) {
-          portal = ReactDOM.unstable_createPortal(
-            <B ref={n => (b = n)} />,
-            bContainer,
-          );
+          portal = ReactDOM.createPortal(<B ref={n => (b = n)} />, bContainer);
         }
         return <div>A{this.state.x}{portal}</div>;
       }
diff --git a/src/renderers/dom/__tests__/ReactDOMProduction-test.js b/src/renderers/dom/__tests__/ReactDOMProduction-test.js
index 422ee37104559..d34da33cc539d 100644
--- a/src/renderers/dom/__tests__/ReactDOMProduction-test.js
+++ b/src/renderers/dom/__tests__/ReactDOMProduction-test.js
@@ -246,10 +246,7 @@ describe('ReactDOMProduction', () => {
       var expectSVG = {ref: el => svgEls.push(el)};
       var expectHTML = {ref: el => htmlEls.push(el)};
       var usePortal = function(tree) {
-        return ReactDOM.unstable_createPortal(
-          tree,
-          document.createElement('div'),
-        );
+        return ReactDOM.createPortal(tree, document.createElement('div'));
       };
       var assertNamespacesMatch = function(tree) {
         var container = document.createElement('div');
diff --git a/src/renderers/dom/fiber/ReactDOMFiberEntry.js b/src/renderers/dom/fiber/ReactDOMFiberEntry.js
index 322a8262dfd3a..4e17cf72d9a8e 100644
--- a/src/renderers/dom/fiber/ReactDOMFiberEntry.js
+++ b/src/renderers/dom/fiber/ReactDOMFiberEntry.js
@@ -646,7 +646,22 @@ function renderSubtreeIntoContainer(
   return DOMRenderer.getPublicRootInstance(root);
 }
 
+function createPortal(
+  children: ReactNodeList,
+  container: DOMContainer,
+  key: ?string = null,
+) {
+  invariant(
+    isValidContainer(container),
+    'Target container is not a DOM element.',
+  );
+  // TODO: pass ReactDOM portal implementation as third argument
+  return ReactPortal.createPortal(children, container, null, key);
+}
+
 var ReactDOMFiber = {
+  createPortal,
+
   hydrate(element: React$Node, container: DOMContainer, callback: ?Function) {
     // TODO: throw or warn if we couldn't hydrate?
     return renderSubtreeIntoContainer(null, element, container, true, callback);
@@ -742,14 +757,9 @@ var ReactDOMFiber = {
 
   findDOMNode: findDOMNode,
 
-  unstable_createPortal(
-    children: ReactNodeList,
-    container: DOMContainer,
-    key: ?string = null,
-  ) {
-    // TODO: pass ReactDOM portal implementation as third argument
-    return ReactPortal.createPortal(children, container, null, key);
-  },
+  // Temporary alias since we already shipped React 16 RC with it.
+  // TODO: remove in React 17.
+  unstable_createPortal: createPortal,
 
   unstable_batchedUpdates: ReactGenericBatching.batchedUpdates,
 
diff --git a/src/renderers/dom/fiber/__tests__/ReactDOMFiber-test.js b/src/renderers/dom/fiber/__tests__/ReactDOMFiber-test.js
index aabaeae11fc41..4c90d2c65496d 100644
--- a/src/renderers/dom/fiber/__tests__/ReactDOMFiber-test.js
+++ b/src/renderers/dom/fiber/__tests__/ReactDOMFiber-test.js
@@ -182,10 +182,7 @@ describe('ReactDOMFiber', () => {
     var expectMath = {ref: el => mathEls.push(el)};
 
     var usePortal = function(tree) {
-      return ReactDOM.unstable_createPortal(
-        tree,
-        document.createElement('div'),
-      );
+      return ReactDOM.createPortal(tree, document.createElement('div'));
     };
 
     var assertNamespacesMatch = function(tree) {
@@ -212,6 +209,24 @@ describe('ReactDOMFiber', () => {
     it('should render one portal', () => {
       var portalContainer = document.createElement('div');
 
+      ReactDOM.render(
+        <div>
+          {ReactDOM.createPortal(<div>portal</div>, portalContainer)}
+        </div>,
+        container,
+      );
+      expect(portalContainer.innerHTML).toBe('<div>portal</div>');
+      expect(container.innerHTML).toBe('<div></div>');
+
+      ReactDOM.unmountComponentAtNode(container);
+      expect(portalContainer.innerHTML).toBe('');
+      expect(container.innerHTML).toBe('');
+    });
+
+    // TODO: remove in React 17
+    it('should support unstable_createPortal alias', () => {
+      var portalContainer = document.createElement('div');
+
       ReactDOM.render(
         <div>
           {ReactDOM.unstable_createPortal(<div>portal</div>, portalContainer)}
@@ -260,12 +275,12 @@ describe('ReactDOMFiber', () => {
           const {step} = this.props;
           return [
             <Child key="a" name={`normal[0]:${step}`} />,
-            ReactDOM.unstable_createPortal(
+            ReactDOM.createPortal(
               <Child key="b" name={`portal1[0]:${step}`} />,
               portalContainer1,
             ),
             <Child key="c" name={`normal[1]:${step}`} />,
-            ReactDOM.unstable_createPortal(
+            ReactDOM.createPortal(
               [
                 <Child key="d" name={`portal2[0]:${step}`} />,
                 <Child key="e" name={`portal2[1]:${step}`} />,
@@ -334,14 +349,14 @@ describe('ReactDOMFiber', () => {
       ReactDOM.render(
         [
           <div key="a">normal[0]</div>,
-          ReactDOM.unstable_createPortal(
+          ReactDOM.createPortal(
             [
               <div key="b">portal1[0]</div>,
-              ReactDOM.unstable_createPortal(
+              ReactDOM.createPortal(
                 <div key="c">portal2[0]</div>,
                 portalContainer2,
               ),
-              ReactDOM.unstable_createPortal(
+              ReactDOM.createPortal(
                 <div key="d">portal3[0]</div>,
                 portalContainer3,
               ),
@@ -374,7 +389,7 @@ describe('ReactDOMFiber', () => {
 
       ReactDOM.render(
         <div>
-          {ReactDOM.unstable_createPortal(<div>portal:1</div>, portalContainer)}
+          {ReactDOM.createPortal(<div>portal:1</div>, portalContainer)}
         </div>,
         container,
       );
@@ -383,7 +398,7 @@ describe('ReactDOMFiber', () => {
 
       ReactDOM.render(
         <div>
-          {ReactDOM.unstable_createPortal(<div>portal:2</div>, portalContainer)}
+          {ReactDOM.createPortal(<div>portal:2</div>, portalContainer)}
         </div>,
         container,
       );
@@ -392,7 +407,7 @@ describe('ReactDOMFiber', () => {
 
       ReactDOM.render(
         <div>
-          {ReactDOM.unstable_createPortal(<p>portal:3</p>, portalContainer)}
+          {ReactDOM.createPortal(<p>portal:3</p>, portalContainer)}
         </div>,
         container,
       );
@@ -401,7 +416,7 @@ describe('ReactDOMFiber', () => {
 
       ReactDOM.render(
         <div>
-          {ReactDOM.unstable_createPortal(['Hi', 'Bye'], portalContainer)}
+          {ReactDOM.createPortal(['Hi', 'Bye'], portalContainer)}
         </div>,
         container,
       );
@@ -410,7 +425,7 @@ describe('ReactDOMFiber', () => {
 
       ReactDOM.render(
         <div>
-          {ReactDOM.unstable_createPortal(['Bye', 'Hi'], portalContainer)}
+          {ReactDOM.createPortal(['Bye', 'Hi'], portalContainer)}
         </div>,
         container,
       );
@@ -419,7 +434,7 @@ describe('ReactDOMFiber', () => {
 
       ReactDOM.render(
         <div>
-          {ReactDOM.unstable_createPortal(null, portalContainer)}
+          {ReactDOM.createPortal(null, portalContainer)}
         </div>,
         container,
       );
@@ -700,7 +715,7 @@ describe('ReactDOMFiber', () => {
         }
 
         render() {
-          return ReactDOM.unstable_createPortal(<Component />, portalContainer);
+          return ReactDOM.createPortal(<Component />, portalContainer);
         }
       }
 
@@ -741,7 +756,7 @@ describe('ReactDOMFiber', () => {
         }
 
         render() {
-          return ReactDOM.unstable_createPortal(<Component />, portalContainer);
+          return ReactDOM.createPortal(<Component />, portalContainer);
         }
       }
 
@@ -781,7 +796,7 @@ describe('ReactDOMFiber', () => {
         }
 
         render() {
-          return ReactDOM.unstable_createPortal(<Component />, portalContainer);
+          return ReactDOM.createPortal(<Component />, portalContainer);
         }
       }
 
@@ -821,7 +836,7 @@ describe('ReactDOMFiber', () => {
 
       ReactDOM.render(
         <div onClick={() => ops.push('parent clicked')}>
-          {ReactDOM.unstable_createPortal(
+          {ReactDOM.createPortal(
             <div
               onClick={() => ops.push('portal clicked')}
               ref={n => (portal = n)}>
@@ -874,7 +889,7 @@ describe('ReactDOMFiber', () => {
             onMouseEnter={() => ops.push('enter parent')}
             onMouseLeave={() => ops.push('leave parent')}>
             <div ref={n => (firstTarget = n)} />
-            {ReactDOM.unstable_createPortal(
+            {ReactDOM.createPortal(
               <div
                 onMouseEnter={() => ops.push('enter portal')}
                 onMouseLeave={() => ops.push('leave portal')}
@@ -909,6 +924,15 @@ describe('ReactDOMFiber', () => {
       ]);
     });
 
+    it('should throw on bad createPortal argument', () => {
+      expect(() => {
+        ReactDOM.createPortal(<div>portal</div>, null);
+      }).toThrow('Target container is not a DOM element.');
+      expect(() => {
+        ReactDOM.createPortal(<div>portal</div>, document.createTextNode('hi'));
+      }).toThrow('Target container is not a DOM element.');
+    });
+
     it('should warn for non-functional event listeners', () => {
       spyOn(console, 'error');
       class Example extends React.Component {
diff --git a/src/renderers/dom/shared/__tests__/renderSubtreeIntoContainer-test.js b/src/renderers/dom/shared/__tests__/renderSubtreeIntoContainer-test.js
index cca63bffa77f1..55b89c036979e 100644
--- a/src/renderers/dom/shared/__tests__/renderSubtreeIntoContainer-test.js
+++ b/src/renderers/dom/shared/__tests__/renderSubtreeIntoContainer-test.js
@@ -319,7 +319,7 @@ describe('renderSubtreeIntoContainer', () => {
           'a React 15 tree inside a React 16 tree using ' +
           "unstable_renderSubtreeIntoContainer, which isn't supported. Try to " +
           'make sure you have only one copy of React (and ideally, switch to ' +
-          'ReactDOM.unstable_createPortal).',
+          'ReactDOM.createPortal).',
       );
     });
   }
diff --git a/src/renderers/native/ReactNativeFiberEntry.js b/src/renderers/native/ReactNativeFiberEntry.js
index d0f119cbde6a2..6c55fdc0a14cc 100644
--- a/src/renderers/native/ReactNativeFiberEntry.js
+++ b/src/renderers/native/ReactNativeFiberEntry.js
@@ -79,7 +79,7 @@ const ReactNativeFiber: ReactNativeType = {
     UIManager.removeRootView(containerTag);
   },
 
-  unstable_createPortal(
+  createPortal(
     children: ReactNodeList,
     containerTag: number,
     key: ?string = null,
diff --git a/src/renderers/shared/fiber/ReactFiberClassComponent.js b/src/renderers/shared/fiber/ReactFiberClassComponent.js
index e726cfd56928e..e9128f5f93b8f 100644
--- a/src/renderers/shared/fiber/ReactFiberClassComponent.js
+++ b/src/renderers/shared/fiber/ReactFiberClassComponent.js
@@ -71,7 +71,7 @@ if (__DEV__) {
           'a React 15 tree inside a React 16 tree using ' +
           "unstable_renderSubtreeIntoContainer, which isn't supported. Try " +
           'to make sure you have only one copy of React (and ideally, switch ' +
-          'to ReactDOM.unstable_createPortal).',
+          'to ReactDOM.createPortal).',
       );
     },
   });