diff --git a/change/@react-native-windows-codegen-1674ebdb-ad8f-432b-bcbc-15b049d1fcc0.json b/change/@react-native-windows-codegen-1674ebdb-ad8f-432b-bcbc-15b049d1fcc0.json
new file mode 100644
index 00000000000..29670771ab9
--- /dev/null
+++ b/change/@react-native-windows-codegen-1674ebdb-ad8f-432b-bcbc-15b049d1fcc0.json
@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "codegen-windows --check always fails",
+  "packageName": "@react-native-windows/codegen",
+  "email": "30809111+acoates-ms@users.noreply.github.com",
+  "dependentChangeType": "patch"
+}
diff --git a/change/react-native-windows-bd661950-16e7-4ff2-bb7a-6927dddb2a28.json b/change/react-native-windows-bd661950-16e7-4ff2-bb7a-6927dddb2a28.json
new file mode 100644
index 00000000000..acb7639a204
--- /dev/null
+++ b/change/react-native-windows-bd661950-16e7-4ff2-bb7a-6927dddb2a28.json
@@ -0,0 +1,7 @@
+{
+  "type": "prerelease",
+  "comment": "Update generated code",
+  "packageName": "react-native-windows",
+  "email": "30809111+acoates-ms@users.noreply.github.com",
+  "dependentChangeType": "patch"
+}
diff --git a/packages/@react-native-windows/codegen/src/Cli.ts b/packages/@react-native-windows/codegen/src/Cli.ts
index 377c8e61371..e3d4cc7453f 100644
--- a/packages/@react-native-windows/codegen/src/Cli.ts
+++ b/packages/@react-native-windows/codegen/src/Cli.ts
@@ -65,4 +65,11 @@ if ((argv.file && argv.files) || (!argv.file && !argv.files)) {
   process.exit(1);
 }
 
-runCodeGen(argv);
+const changesNecessary = runCodeGen(argv);
+
+if (argv.test && changesNecessary) {
+  console.error(
+    'There is a change in the output of codegen.  Rerun "react-native codegen-windows" to regenerate.',
+  );
+  process.exit(2);
+}
diff --git a/packages/@react-native-windows/codegen/src/index.ts b/packages/@react-native-windows/codegen/src/index.ts
index 479e56c893f..bb591169aee 100644
--- a/packages/@react-native-windows/codegen/src/index.ts
+++ b/packages/@react-native-windows/codegen/src/index.ts
@@ -65,15 +65,20 @@ function checkFilesForChanges(
 ): boolean {
   let hasChanges = false;
 
+  outputDir = path.resolve(outputDir);
+  const globbyDir = outputDir.replace(/\\/g, '/');
   const allExistingFiles = globby
-    .sync(`${outputDir}/**`)
-    .map(_ => path.normalize(_))
-    .sort();
+    .sync([`${globbyDir}/**`, `${globbyDir}/**/.*`], {absolute: true})
+    .map(_ => path.normalize(_));
   const allGeneratedFiles = [...map.keys()].map(_ => path.normalize(_)).sort();
 
   if (
     allExistingFiles.length !== allGeneratedFiles.length ||
-    !allExistingFiles.every((val, index) => val === allGeneratedFiles[index])
+    !allGeneratedFiles.every(filepath =>
+      allExistingFiles.includes(
+        path.normalize(path.resolve(process.cwd(), filepath)),
+      ),
+    )
   )
     return true;
 
@@ -97,10 +102,19 @@ function checkFilesForChanges(
 function writeMapToFiles(map: Map<string, string>, outputDir: string) {
   let success = true;
 
+  outputDir = path.resolve(outputDir);
+  const globbyDir = outputDir.replace(/\\/g, '/');
+
   // This ensures that we delete any generated files from modules that have been deleted
-  const allExistingFiles = globby.sync(`${outputDir}/**`);
+  const allExistingFiles = globby.sync(
+    [`${globbyDir}/**`, `${globbyDir}/**/.*`],
+    {absolute: true},
+  );
+
+  const allGeneratedFiles = [...map.keys()].map(_ => path.normalize(_)).sort();
   allExistingFiles.forEach(existingFile => {
-    if (!map.has(path.normalize(existingFile))) {
+    if (!allGeneratedFiles.includes(path.normalize(existingFile))) {
+      console.log('Deleting ', existingFile);
       fs.unlinkSync(existingFile);
     }
   });
@@ -117,6 +131,7 @@ function writeMapToFiles(map: Map<string, string>, outputDir: string) {
         }
       }
 
+      console.log('Writing ', fileName);
       fs.writeFileSync(fileName, contents);
     } catch (error) {
       success = false;
diff --git a/packages/sample-apps/just-task.js b/packages/sample-apps/just-task.js
index 38d106559f1..e1c1c7e8715 100644
--- a/packages/sample-apps/just-task.js
+++ b/packages/sample-apps/just-task.js
@@ -5,7 +5,7 @@
  * @ts-check
  */
 
-const {task, series} = require('just-scripts');
+const {task, series, parallel} = require('just-scripts');
 const fs = require('fs');
 const {execSync} = require('child_process');
 
@@ -16,6 +16,12 @@ task('codegen', () => {
   execSync('npx react-native codegen-windows --logging', {env: process.env});
 });
 
+task('codegen:check', () => {
+  execSync('npx react-native codegen-windows --logging --check', {
+    env: process.env,
+  });
+});
+
 task('prepareBundle', () => {
   fs.mkdirSync('windows/SampleAppCS/Bundle', {recursive: true});
   fs.mkdirSync('windows/SampleAppCPP/Bundle', {recursive: true});
diff --git a/vnext/just-task.js b/vnext/just-task.js
index 4ed56d4e1f7..a5d456e315b 100644
--- a/vnext/just-task.js
+++ b/vnext/just-task.js
@@ -25,16 +25,23 @@ const fs = require('fs');
 option('production');
 option('clean');
 
-task('codegen', () => {
+function codegen(test) {
   execSync(
-    'react-native-windows-codegen --files Libraries/**/*Native*.js --namespace Microsoft::ReactNativeSpecs --libraryName rnwcore --modulesWindows --modulesCxx',
+    `react-native-windows-codegen --files Libraries/**/*Native*.js --namespace Microsoft::ReactNativeSpecs --libraryName rnwcore --modulesWindows --modulesCxx${
+      test ? ' --test' : ''
+    }`,
     {env: process.env},
   );
   execSync(
-    'react-native-windows-codegen --files Microsoft.ReactNative.IntegrationTests/**/*Native*.js --namespace Microsoft::ReactNativeIntegrationTestSpecs --libraryName msrnIntegrationTests --modulesCxx --outputDirectory Microsoft.ReactNative.IntegrationTests/codegen',
+    `react-native-windows-codegen --files Microsoft.ReactNative.IntegrationTests/**/*Native*.js --namespace Microsoft::ReactNativeIntegrationTestSpecs --libraryName msrnIntegrationTests --modulesCxx --outputDirectory Microsoft.ReactNative.IntegrationTests/codegen${
+      test ? ' --test' : ''
+    }`,
     {env: process.env},
   );
-});
+}
+
+task('codegen', () => codegen(false));
+task('codegen:check', () => codegen(true));
 
 task('copyReadmeAndLicenseFromRoot', () => {
   fs.copyFileSync(
@@ -62,4 +69,4 @@ task(
 
 task('clean', series('cleanRNLibraries'));
 
-task('lint', series('eslint', 'flow-check'));
+task('lint', series('eslint', 'codegen:check', 'flow-check'));