diff --git a/packages/react-art/src/ReactARTHostConfig.js b/packages/react-art/src/ReactARTHostConfig.js
index 47bced8a1274a..b1f80ccc2be85 100644
--- a/packages/react-art/src/ReactARTHostConfig.js
+++ b/packages/react-art/src/ReactARTHostConfig.js
@@ -451,3 +451,7 @@ export function preparePortalMount(portalInstance: any): void {
 export function detachDeletedInstance(node: Instance): void {
   // noop
 }
+
+export function logHydrationError(config, error) {
+  // noop
+}
diff --git a/packages/react-dom/src/__tests__/ReactDOMFizzServer-test.js b/packages/react-dom/src/__tests__/ReactDOMFizzServer-test.js
index d8db609f3f2cf..bcf0aaa461628 100644
--- a/packages/react-dom/src/__tests__/ReactDOMFizzServer-test.js
+++ b/packages/react-dom/src/__tests__/ReactDOMFizzServer-test.js
@@ -1897,9 +1897,15 @@ describe('ReactDOMFizzServer', () => {
       // Hydrate the tree. Child will throw during hydration, but not when it
       // falls back to client rendering.
       isClient = true;
-      ReactDOM.hydrateRoot(container, <App />);
+      ReactDOM.hydrateRoot(container, <App />, {
+        onHydrationError(error) {
+          Scheduler.unstable_yieldValue(error.message);
+        },
+      });
 
-      expect(Scheduler).toFlushAndYield(['Yay!']);
+      // An error logged but instead of surfacing it to the UI, we switched
+      // to client rendering.
+      expect(Scheduler).toFlushAndYield(['Yay!', 'Hydration error']);
       expect(getVisibleChildren(container)).toEqual(
         <div>
           <span />
@@ -1975,9 +1981,16 @@ describe('ReactDOMFizzServer', () => {
 
       // Hydrate the tree. Child will throw during render.
       isClient = true;
-      ReactDOM.hydrateRoot(container, <App />);
+      ReactDOM.hydrateRoot(container, <App />, {
+        onHydrationError(error) {
+          // TODO: We logged a hydration error, but the same error ends up
+          // being thrown during the fallback to client rendering, too. Maybe
+          // we should only log if the client render succeeds.
+          Scheduler.unstable_yieldValue(error.message);
+        },
+      });
 
-      expect(Scheduler).toFlushAndYield([]);
+      expect(Scheduler).toFlushAndYield(['Oops!']);
       expect(getVisibleChildren(container)).toEqual('Oops!');
     },
   );
@@ -2049,9 +2062,15 @@ describe('ReactDOMFizzServer', () => {
       // Hydrate the tree. Child will throw during hydration, but not when it
       // falls back to client rendering.
       isClient = true;
-      ReactDOM.hydrateRoot(container, <App />);
+      ReactDOM.hydrateRoot(container, <App />, {
+        onHydrationError(error) {
+          Scheduler.unstable_yieldValue(error.message);
+        },
+      });
 
-      expect(Scheduler).toFlushAndYield([]);
+      // An error logged but instead of surfacing it to the UI, we switched
+      // to client rendering.
+      expect(Scheduler).toFlushAndYield(['Hydration error']);
       expect(getVisibleChildren(container)).toEqual(
         <div>
           <span />
diff --git a/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js b/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
index 1c65501f7b382..1a98b8e8f877e 100644
--- a/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
+++ b/packages/react-dom/src/__tests__/ReactDOMServerPartialHydration-test.internal.js
@@ -208,9 +208,17 @@ describe('ReactDOMServerPartialHydration', () => {
     // On the client we don't have all data yet but we want to start
     // hydrating anyway.
     suspend = true;
-    ReactDOM.hydrateRoot(container, <App />);
+    ReactDOM.hydrateRoot(container, <App />, {
+      onHydrationError(error) {
+        Scheduler.unstable_yieldValue(error.message);
+      },
+    });
     if (gate(flags => flags.enableClientRenderFallbackOnHydrationMismatch)) {
-      Scheduler.unstable_flushAll();
+      // Hydration error is logged
+      expect(Scheduler).toFlushAndYield([
+        'An error occurred during hydration. The server HTML was replaced ' +
+          'with client content',
+      ]);
     } else {
       expect(() => {
         Scheduler.unstable_flushAll();
@@ -290,13 +298,24 @@ describe('ReactDOMServerPartialHydration', () => {
     suspend = true;
     client = true;
 
-    ReactDOM.hydrateRoot(container, <App />);
+    ReactDOM.hydrateRoot(container, <App />, {
+      onHydrationError(error) {
+        Scheduler.unstable_yieldValue(error.message);
+      },
+    });
     expect(Scheduler).toFlushAndYield([
       'Suspend',
       'Component',
       'Component',
       'Component',
       'Component',
+
+      // Hydration mismatch errors are logged.
+      // TODO: This could get noisy. Is there some way to dedupe?
+      'An error occurred during hydration. The server HTML was replaced with client content',
+      'An error occurred during hydration. The server HTML was replaced with client content',
+      'An error occurred during hydration. The server HTML was replaced with client content',
+      'An error occurred during hydration. The server HTML was replaced with client content',
     ]);
     jest.runAllTimers();
 
@@ -316,12 +335,16 @@ describe('ReactDOMServerPartialHydration', () => {
       'Component',
       'Component',
       'Component',
+
       // second pass as client render
       'Hello',
       'Component',
       'Component',
       'Component',
       'Component',
+
+      // Hydration mismatch is logged
+      'An error occurred during hydration. The server HTML was replaced with client content',
     ]);
 
     // Client rendered - suspense comment nodes removed
diff --git a/packages/react-dom/src/client/ReactDOMHostConfig.js b/packages/react-dom/src/client/ReactDOMHostConfig.js
index 341d1fa7a3764..cd2fad2fdb873 100644
--- a/packages/react-dom/src/client/ReactDOMHostConfig.js
+++ b/packages/react-dom/src/client/ReactDOMHostConfig.js
@@ -70,6 +70,7 @@ import {HostComponent, HostText} from 'react-reconciler/src/ReactWorkTags';
 import {listenToAllSupportedEvents} from '../events/DOMPluginEventSystem';
 
 import {DefaultEventPriority} from 'react-reconciler/src/ReactEventPriorities';
+import {scheduleCallback, IdlePriority} from 'react-reconciler/src/Scheduler';
 
 export type Type = string;
 export type Props = {
@@ -123,6 +124,10 @@ export type TimeoutHandle = TimeoutID;
 export type NoTimeout = -1;
 export type RendererInspectionConfig = $ReadOnly<{||}>;
 
+// Right now this is a single callback, but could be multiple in the in the
+// future.
+export type ErrorLoggingConfig = null | ((error: mixed) => void);
+
 type SelectionInformation = {|
   focusedElem: null | HTMLElement,
   selectionRange: mixed,
@@ -374,6 +379,25 @@ export function getCurrentEventPriority(): * {
   return getEventPriority(currentEvent.type);
 }
 
+export function logHydrationError(
+  config: ErrorLoggingConfig,
+  error: mixed,
+): void {
+  const onHydrationError = config;
+  if (onHydrationError !== null) {
+    // Schedule a callback to invoke the user-provided logging function.
+    scheduleCallback(IdlePriority, () => {
+      onHydrationError(error);
+    });
+  } else {
+    // Default behavior is to rethrow the error in a separate task. This will
+    // trigger a browser error event.
+    scheduleCallback(IdlePriority, () => {
+      throw error;
+    });
+  }
+}
+
 export const isPrimaryRenderer = true;
 export const warnsIfNotActing = true;
 // This initialization code may run even on server environments
diff --git a/packages/react-dom/src/client/ReactDOMLegacy.js b/packages/react-dom/src/client/ReactDOMLegacy.js
index 05ae0d5ce4f45..cb95101401ea4 100644
--- a/packages/react-dom/src/client/ReactDOMLegacy.js
+++ b/packages/react-dom/src/client/ReactDOMLegacy.js
@@ -122,6 +122,7 @@ function legacyCreateRootFromDOMContainer(
     false, // isStrictMode
     false, // concurrentUpdatesByDefaultOverride,
     '', // identifierPrefix
+    null,
   );
   markContainerAsRoot(root.current, container);
 
diff --git a/packages/react-dom/src/client/ReactDOMRoot.js b/packages/react-dom/src/client/ReactDOMRoot.js
index 800eeba0d018d..caf1f78c4801c 100644
--- a/packages/react-dom/src/client/ReactDOMRoot.js
+++ b/packages/react-dom/src/client/ReactDOMRoot.js
@@ -36,6 +36,7 @@ export type HydrateRootOptions = {
   unstable_strictMode?: boolean,
   unstable_concurrentUpdatesByDefault?: boolean,
   identifierPrefix?: string,
+  onHydrationError?: (error: mixed) => void,
   ...
 };
 
@@ -173,6 +174,7 @@ export function createRoot(
     isStrictMode,
     concurrentUpdatesByDefaultOverride,
     identifierPrefix,
+    null,
   );
   markContainerAsRoot(root.current, container);
 
@@ -213,6 +215,7 @@ export function hydrateRoot(
   let isStrictMode = false;
   let concurrentUpdatesByDefaultOverride = false;
   let identifierPrefix = '';
+  let onHydrationError = null;
   if (options !== null && options !== undefined) {
     if (options.unstable_strictMode === true) {
       isStrictMode = true;
@@ -226,6 +229,9 @@ export function hydrateRoot(
     if (options.identifierPrefix !== undefined) {
       identifierPrefix = options.identifierPrefix;
     }
+    if (options.onHydrationError !== undefined) {
+      onHydrationError = options.onHydrationError;
+    }
   }
 
   const root = createContainer(
@@ -236,6 +242,7 @@ export function hydrateRoot(
     isStrictMode,
     concurrentUpdatesByDefaultOverride,
     identifierPrefix,
+    onHydrationError,
   );
   markContainerAsRoot(root.current, container);
   // This can't be a comment node since hydration doesn't work on comment nodes anyway.
diff --git a/packages/react-native-renderer/src/ReactFabric.js b/packages/react-native-renderer/src/ReactFabric.js
index bf7754d6099c2..25cbd31b9fdf5 100644
--- a/packages/react-native-renderer/src/ReactFabric.js
+++ b/packages/react-native-renderer/src/ReactFabric.js
@@ -214,6 +214,7 @@ function render(
       false,
       null,
       '',
+      null,
     );
     roots.set(containerTag, root);
   }
diff --git a/packages/react-native-renderer/src/ReactFabricHostConfig.js b/packages/react-native-renderer/src/ReactFabricHostConfig.js
index 727b782efd768..3d2f890387678 100644
--- a/packages/react-native-renderer/src/ReactFabricHostConfig.js
+++ b/packages/react-native-renderer/src/ReactFabricHostConfig.js
@@ -95,6 +95,8 @@ export type RendererInspectionConfig = $ReadOnly<{|
   ) => void,
 |}>;
 
+export type ErrorLoggingConfig = null;
+
 // TODO: Remove this conditional once all changes have propagated.
 if (registerEventHandler) {
   /**
@@ -525,3 +527,10 @@ export function preparePortalMount(portalInstance: Instance): void {
 export function detachDeletedInstance(node: Instance): void {
   // noop
 }
+
+export function logHydrationError(
+  config: ErrorLoggingConfig,
+  error: mixed,
+): void {
+  // noop
+}
diff --git a/packages/react-native-renderer/src/ReactNativeHostConfig.js b/packages/react-native-renderer/src/ReactNativeHostConfig.js
index 10c5e37f41bcc..bc7c859c4c858 100644
--- a/packages/react-native-renderer/src/ReactNativeHostConfig.js
+++ b/packages/react-native-renderer/src/ReactNativeHostConfig.js
@@ -55,6 +55,8 @@ export type RendererInspectionConfig = $ReadOnly<{|
   ) => void,
 |}>;
 
+export type ErrorLoggingConfig = null;
+
 const UPDATE_SIGNAL = {};
 if (__DEV__) {
   Object.freeze(UPDATE_SIGNAL);
@@ -513,3 +515,10 @@ export function preparePortalMount(portalInstance: Instance): void {
 export function detachDeletedInstance(node: Instance): void {
   // noop
 }
+
+export function logHydrationError(
+  config: ErrorLoggingConfig,
+  error: mixed,
+): void {
+  // noop
+}
diff --git a/packages/react-native-renderer/src/ReactNativeRenderer.js b/packages/react-native-renderer/src/ReactNativeRenderer.js
index fb539d8996811..c5d4318311c0b 100644
--- a/packages/react-native-renderer/src/ReactNativeRenderer.js
+++ b/packages/react-native-renderer/src/ReactNativeRenderer.js
@@ -210,6 +210,7 @@ function render(
       false,
       null,
       '',
+      null,
     );
     roots.set(containerTag, root);
   }
diff --git a/packages/react-noop-renderer/src/createReactNoop.js b/packages/react-noop-renderer/src/createReactNoop.js
index ef76b6610617f..c93b5eb6e91dd 100644
--- a/packages/react-noop-renderer/src/createReactNoop.js
+++ b/packages/react-noop-renderer/src/createReactNoop.js
@@ -466,6 +466,10 @@ function createReactNoop(reconciler: Function, useMutation: boolean) {
     },
 
     detachDeletedInstance() {},
+
+    logHydrationError() {
+      // no-op
+    },
   };
 
   const hostConfig = useMutation
diff --git a/packages/react-reconciler/src/ReactFiberReconciler.new.js b/packages/react-reconciler/src/ReactFiberReconciler.new.js
index 1cf200e35d56d..93a3e13bef85a 100644
--- a/packages/react-reconciler/src/ReactFiberReconciler.new.js
+++ b/packages/react-reconciler/src/ReactFiberReconciler.new.js
@@ -15,6 +15,7 @@ import type {
   TextInstance,
   Container,
   PublicInstance,
+  ErrorLoggingConfig,
 } from './ReactFiberHostConfig';
 import type {RendererInspectionConfig} from './ReactFiberHostConfig';
 import type {ReactNodeList} from 'shared/ReactTypes';
@@ -245,6 +246,7 @@ export function createContainer(
   isStrictMode: boolean,
   concurrentUpdatesByDefaultOverride: null | boolean,
   identifierPrefix: string,
+  errorLoggingConfig: ErrorLoggingConfig,
 ): OpaqueRoot {
   return createFiberRoot(
     containerInfo,
@@ -254,6 +256,7 @@ export function createContainer(
     isStrictMode,
     concurrentUpdatesByDefaultOverride,
     identifierPrefix,
+    errorLoggingConfig,
   );
 }
 
diff --git a/packages/react-reconciler/src/ReactFiberReconciler.old.js b/packages/react-reconciler/src/ReactFiberReconciler.old.js
index 4b02959ab0840..0fcba6293c7b7 100644
--- a/packages/react-reconciler/src/ReactFiberReconciler.old.js
+++ b/packages/react-reconciler/src/ReactFiberReconciler.old.js
@@ -15,6 +15,7 @@ import type {
   TextInstance,
   Container,
   PublicInstance,
+  ErrorLoggingConfig,
 } from './ReactFiberHostConfig';
 import type {RendererInspectionConfig} from './ReactFiberHostConfig';
 import type {ReactNodeList} from 'shared/ReactTypes';
@@ -245,6 +246,7 @@ export function createContainer(
   isStrictMode: boolean,
   concurrentUpdatesByDefaultOverride: null | boolean,
   identifierPrefix: string,
+  errorLoggingConfig: ErrorLoggingConfig,
 ): OpaqueRoot {
   return createFiberRoot(
     containerInfo,
@@ -254,6 +256,7 @@ export function createContainer(
     isStrictMode,
     concurrentUpdatesByDefaultOverride,
     identifierPrefix,
+    errorLoggingConfig,
   );
 }
 
diff --git a/packages/react-reconciler/src/ReactFiberRoot.new.js b/packages/react-reconciler/src/ReactFiberRoot.new.js
index 9e9feb45d9b03..dd5e6a5fc7da0 100644
--- a/packages/react-reconciler/src/ReactFiberRoot.new.js
+++ b/packages/react-reconciler/src/ReactFiberRoot.new.js
@@ -9,6 +9,7 @@
 
 import type {FiberRoot, SuspenseHydrationCallbacks} from './ReactInternalTypes';
 import type {RootTag} from './ReactRootTags';
+import type {ErrorLoggingConfig} from './ReactFiberHostConfig';
 
 import {noTimeout, supportsHydration} from './ReactFiberHostConfig';
 import {createHostRootFiber} from './ReactFiber.new';
@@ -30,7 +31,13 @@ import {initializeUpdateQueue} from './ReactUpdateQueue.new';
 import {LegacyRoot, ConcurrentRoot} from './ReactRootTags';
 import {createCache, retainCache} from './ReactFiberCacheComponent.new';
 
-function FiberRootNode(containerInfo, tag, hydrate, identifierPrefix) {
+function FiberRootNode(
+  containerInfo,
+  tag,
+  hydrate,
+  identifierPrefix,
+  errorLoggingConfig,
+) {
   this.tag = tag;
   this.containerInfo = containerInfo;
   this.pendingChildren = null;
@@ -57,6 +64,7 @@ function FiberRootNode(containerInfo, tag, hydrate, identifierPrefix) {
   this.entanglements = createLaneMap(NoLanes);
 
   this.identifierPrefix = identifierPrefix;
+  this.errorLoggingConfig = errorLoggingConfig;
 
   if (enableCache) {
     this.pooledCache = null;
@@ -103,13 +111,19 @@ export function createFiberRoot(
   hydrationCallbacks: null | SuspenseHydrationCallbacks,
   isStrictMode: boolean,
   concurrentUpdatesByDefaultOverride: null | boolean,
+  // TODO: We have several of these arguments that are conceptually part of the
+  // host config, but because they are passed in at runtime, we have to thread
+  // them through the root constructor. Perhaps we should put them all into a
+  // single type, like a DynamicHostConfig that is defined by the renderer.
   identifierPrefix: string,
+  errorLoggingConfig: ErrorLoggingConfig,
 ): FiberRoot {
   const root: FiberRoot = (new FiberRootNode(
     containerInfo,
     tag,
     hydrate,
     identifierPrefix,
+    errorLoggingConfig,
   ): any);
   if (enableSuspenseCallback) {
     root.hydrationCallbacks = hydrationCallbacks;
diff --git a/packages/react-reconciler/src/ReactFiberRoot.old.js b/packages/react-reconciler/src/ReactFiberRoot.old.js
index d8d061297854f..d6791e97c34fd 100644
--- a/packages/react-reconciler/src/ReactFiberRoot.old.js
+++ b/packages/react-reconciler/src/ReactFiberRoot.old.js
@@ -9,6 +9,7 @@
 
 import type {FiberRoot, SuspenseHydrationCallbacks} from './ReactInternalTypes';
 import type {RootTag} from './ReactRootTags';
+import type {ErrorLoggingConfig} from './ReactFiberHostConfig';
 
 import {noTimeout, supportsHydration} from './ReactFiberHostConfig';
 import {createHostRootFiber} from './ReactFiber.old';
@@ -30,7 +31,13 @@ import {initializeUpdateQueue} from './ReactUpdateQueue.old';
 import {LegacyRoot, ConcurrentRoot} from './ReactRootTags';
 import {createCache, retainCache} from './ReactFiberCacheComponent.old';
 
-function FiberRootNode(containerInfo, tag, hydrate, identifierPrefix) {
+function FiberRootNode(
+  containerInfo,
+  tag,
+  hydrate,
+  identifierPrefix,
+  errorLoggingConfig,
+) {
   this.tag = tag;
   this.containerInfo = containerInfo;
   this.pendingChildren = null;
@@ -57,6 +64,7 @@ function FiberRootNode(containerInfo, tag, hydrate, identifierPrefix) {
   this.entanglements = createLaneMap(NoLanes);
 
   this.identifierPrefix = identifierPrefix;
+  this.errorLoggingConfig = errorLoggingConfig;
 
   if (enableCache) {
     this.pooledCache = null;
@@ -103,13 +111,19 @@ export function createFiberRoot(
   hydrationCallbacks: null | SuspenseHydrationCallbacks,
   isStrictMode: boolean,
   concurrentUpdatesByDefaultOverride: null | boolean,
+  // TODO: We have several of these arguments that are conceptually part of the
+  // host config, but because they are passed in at runtime, we have to thread
+  // them through the root constructor. Perhaps we should put them all into a
+  // single type, like a DynamicHostConfig that is defined by the renderer.
   identifierPrefix: string,
+  errorLoggingConfig: ErrorLoggingConfig,
 ): FiberRoot {
   const root: FiberRoot = (new FiberRootNode(
     containerInfo,
     tag,
     hydrate,
     identifierPrefix,
+    errorLoggingConfig,
   ): any);
   if (enableSuspenseCallback) {
     root.hydrationCallbacks = hydrationCallbacks;
diff --git a/packages/react-reconciler/src/ReactFiberThrow.new.js b/packages/react-reconciler/src/ReactFiberThrow.new.js
index cd9931687ba5a..60903d236e0d5 100644
--- a/packages/react-reconciler/src/ReactFiberThrow.new.js
+++ b/packages/react-reconciler/src/ReactFiberThrow.new.js
@@ -37,6 +37,7 @@ import {
 import {
   supportsPersistence,
   getOffscreenContainerProps,
+  logHydrationError,
 } from './ReactFiberHostConfig';
 import {shouldCaptureSuspense} from './ReactFiberSuspenseComponent.new';
 import {NoMode, ConcurrentMode, DebugTracingMode} from './ReactTypeOfMode';
@@ -507,6 +508,14 @@ function throwException(
           root,
           rootRenderLanes,
         );
+
+        // Even though the user may not be affected by this error, we should
+        // still log it so it can be fixed.
+        // TODO: For now, we only log errors that occur during hydration, but we
+        // probably want to log any error that is recovered from without
+        // triggering an error boundary — or maybe even those, too. Need to
+        // figure out the right API.
+        logHydrationError(root.errorLoggingConfig, value);
         return;
       }
     } else {
diff --git a/packages/react-reconciler/src/ReactFiberThrow.old.js b/packages/react-reconciler/src/ReactFiberThrow.old.js
index 8f6d18a48dea3..6b7f4bf6055b4 100644
--- a/packages/react-reconciler/src/ReactFiberThrow.old.js
+++ b/packages/react-reconciler/src/ReactFiberThrow.old.js
@@ -37,6 +37,7 @@ import {
 import {
   supportsPersistence,
   getOffscreenContainerProps,
+  logHydrationError,
 } from './ReactFiberHostConfig';
 import {shouldCaptureSuspense} from './ReactFiberSuspenseComponent.old';
 import {NoMode, ConcurrentMode, DebugTracingMode} from './ReactTypeOfMode';
@@ -507,6 +508,14 @@ function throwException(
           root,
           rootRenderLanes,
         );
+
+        // Even though the user may not be affected by this error, we should
+        // still log it so it can be fixed.
+        // TODO: For now, we only log errors that occur during hydration, but we
+        // probably want to log any error that is recovered from without
+        // triggering an error boundary — or maybe even those, too. Need to
+        // figure out the right API.
+        logHydrationError(root.errorLoggingConfig, value);
         return;
       }
     } else {
diff --git a/packages/react-reconciler/src/ReactInternalTypes.js b/packages/react-reconciler/src/ReactInternalTypes.js
index 13965720b7cd3..1cc2128356090 100644
--- a/packages/react-reconciler/src/ReactInternalTypes.js
+++ b/packages/react-reconciler/src/ReactInternalTypes.js
@@ -16,7 +16,10 @@ import type {
   MutableSourceVersion,
   MutableSource,
 } from 'shared/ReactTypes';
-import type {SuspenseInstance} from './ReactFiberHostConfig';
+import type {
+  SuspenseInstance,
+  ErrorLoggingConfig,
+} from './ReactFiberHostConfig';
 import type {WorkTag} from './ReactWorkTags';
 import type {TypeOfMode} from './ReactTypeOfMode';
 import type {Flags} from './ReactFiberFlags';
@@ -246,6 +249,8 @@ type BaseFiberRootProperties = {|
   // the public createRoot object, which the fiber tree does not currently have
   // a reference to.
   identifierPrefix: string,
+
+  errorLoggingConfig: ErrorLoggingConfig,
 |};
 
 // The following attributes are only used by DevTools and are only present in DEV builds.
diff --git a/packages/react-reconciler/src/__tests__/ReactFiberHostContext-test.internal.js b/packages/react-reconciler/src/__tests__/ReactFiberHostContext-test.internal.js
index 4bf292df79f7a..d0c3d5b236ea4 100644
--- a/packages/react-reconciler/src/__tests__/ReactFiberHostContext-test.internal.js
+++ b/packages/react-reconciler/src/__tests__/ReactFiberHostContext-test.internal.js
@@ -76,6 +76,7 @@ describe('ReactFiberHostContext', () => {
       null,
       false,
       '',
+      null,
     );
     act(() => {
       Renderer.updateContainer(
@@ -139,6 +140,7 @@ describe('ReactFiberHostContext', () => {
       null,
       false,
       '',
+      null,
     );
     act(() => {
       Renderer.updateContainer(
diff --git a/packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js b/packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js
index 6535d8d3fdec3..2f86a13dc3535 100644
--- a/packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js
+++ b/packages/react-reconciler/src/forks/ReactFiberHostConfig.custom.js
@@ -38,6 +38,7 @@ export opaque type ChildSet = mixed; // eslint-disable-line no-undef
 export opaque type TimeoutHandle = mixed; // eslint-disable-line no-undef
 export opaque type NoTimeout = mixed; // eslint-disable-line no-undef
 export opaque type RendererInspectionConfig = mixed; // eslint-disable-line no-undef
+export opaque type ErrorCallbackConfig = mixed; // eslint-disable-line no-undef
 export type EventResponder = any;
 
 export const getPublicInstance = $$$hostConfig.getPublicInstance;
@@ -68,6 +69,7 @@ export const prepareScopeUpdate = $$$hostConfig.preparePortalMount;
 export const getInstanceFromScope = $$$hostConfig.getInstanceFromScope;
 export const getCurrentEventPriority = $$$hostConfig.getCurrentEventPriority;
 export const detachDeletedInstance = $$$hostConfig.detachDeletedInstance;
+export const onHydrationError = $$$hostConfig.errorHydratingContainer;
 
 // -------------------
 //      Microtasks
diff --git a/packages/react-test-renderer/src/ReactTestHostConfig.js b/packages/react-test-renderer/src/ReactTestHostConfig.js
index 503b08efaf20b..5279fda0b43f6 100644
--- a/packages/react-test-renderer/src/ReactTestHostConfig.js
+++ b/packages/react-test-renderer/src/ReactTestHostConfig.js
@@ -42,6 +42,8 @@ export type EventResponder = any;
 
 export type RendererInspectionConfig = $ReadOnly<{||}>;
 
+export type ErrorLoggingConfig = null;
+
 export * from 'react-reconciler/src/ReactFiberHostConfigWithNoPersistence';
 export * from 'react-reconciler/src/ReactFiberHostConfigWithNoHydration';
 export * from 'react-reconciler/src/ReactFiberHostConfigWithNoTestSelectors';
@@ -314,3 +316,10 @@ export function getInstanceFromScope(scopeInstance: Object): null | Object {
 export function detachDeletedInstance(node: Instance): void {
   // noop
 }
+
+export function logHydrationError(
+  config: ErrorLoggingConfig,
+  error: mixed,
+): void {
+  // noop
+}
diff --git a/packages/react-test-renderer/src/ReactTestRenderer.js b/packages/react-test-renderer/src/ReactTestRenderer.js
index de6e4beffec5f..a8121d1a14fcf 100644
--- a/packages/react-test-renderer/src/ReactTestRenderer.js
+++ b/packages/react-test-renderer/src/ReactTestRenderer.js
@@ -472,6 +472,7 @@ function create(element: React$Element<any>, options: TestRendererOptions) {
     isStrictMode,
     concurrentUpdatesByDefault,
     '',
+    null,
   );
 
   if (root == null) {