diff --git a/.github/workflows/locales-lint.yml b/.github/workflows/locales-lint.yml
new file mode 100644
index 0000000000..db2c66f7b8
--- /dev/null
+++ b/.github/workflows/locales-lint.yml
@@ -0,0 +1,34 @@
+---
+name: Locales lint for Crowdin
+
+on:
+  pull_request:
+    branches-ignore:
+      - 'l10n_master'
+      - 'cf-pages'
+    paths:
+      - '**/messages.json'
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-22.04
+    steps:
+      - name: Checkout repo
+        uses: actions/checkout@d632683dd7b4114ad314bca15554477dd762a938 # v4.2.0
+      - name: Checkout base branch repo
+        uses: actions/checkout@d632683dd7b4114ad314bca15554477dd762a938 # v4.2.0
+        with:
+          ref: ${{ github.event.pull_request.base.sha }}
+          path: base
+      - name: Install dependencies
+        run: npm ci
+      - name: Compare
+        run: |
+          npm run test:locales
+          if [ $? -eq 0 ]; then
+            echo "Lint check successful."
+          else
+            echo "Lint check failed."
+            exit 1
+          fi
diff --git a/package.json b/package.json
index 2926fd095f..6e4e6c1199 100644
--- a/package.json
+++ b/package.json
@@ -22,6 +22,7 @@
     "test:watch": "jest --clearCache && jest --watch",
     "test:watch:all": "jest --watchAll",
     "test:types": "node ./scripts/test-types.js",
+    "test:locales": "tsc --project ./scripts/tsconfig.json && node ./scripts/dist/test-locales.js",
     "docs:json": "compodoc -p ./tsconfig.json -e json -d . --disableRoutesGraph",
     "storybook": "ng run components:storybook",
     "build-storybook": "ng run components:build-storybook",
diff --git a/scripts/.eslintrc.json b/scripts/.eslintrc.json
new file mode 100644
index 0000000000..10d2238837
--- /dev/null
+++ b/scripts/.eslintrc.json
@@ -0,0 +1,5 @@
+{
+  "env": {
+    "node": true
+  }
+}
diff --git a/scripts/test-locales.ts b/scripts/test-locales.ts
new file mode 100644
index 0000000000..85ed6e7afa
--- /dev/null
+++ b/scripts/test-locales.ts
@@ -0,0 +1,105 @@
+/* eslint no-console:0 */
+import fs from "fs";
+import path from "path";
+
+type Messages = {
+  [id: string]: {
+    message: string;
+  };
+};
+
+function findLocaleFiles(dir: string): string[] {
+  return fs
+    .readdirSync(dir, { encoding: null, recursive: true })
+    .filter((file) => path.basename(file) === "messages.json")
+    .filter((file) => path.dirname(file).endsWith("en"))
+    .map((file) => path.join(dir, file));
+}
+
+function findAllLocaleFiles(rootDir: string): string[] {
+  return [
+    ...findLocaleFiles(path.join(rootDir, "apps", "browser", "src")),
+    ...findLocaleFiles(path.join(rootDir, "apps", "cli", "src")),
+    ...findLocaleFiles(path.join(rootDir, "apps", "desktop", "src")),
+    ...findLocaleFiles(path.join(rootDir, "apps", "web", "src")),
+  ].map((file) => path.relative(rootDir, file));
+}
+
+function readMessagesJson(file: string): Messages {
+  let content = fs.readFileSync(file, { encoding: "utf-8" });
+  // Strip BOM
+  content = content.replace(/^\uFEFF/, "");
+  try {
+    return JSON.parse(content);
+  } catch (e: unknown) {
+    console.error(`ERROR: Invalid JSON file ${file}`, e);
+    throw e;
+  }
+}
+
+function compareMessagesJson(beforeFile: string, afterFile: string): boolean {
+  try {
+    console.log("Comparing locale files:", beforeFile, afterFile);
+
+    const messagesBeforeJson = readMessagesJson(beforeFile);
+    const messagesAfterJson = readMessagesJson(afterFile);
+
+    const messagesIdMapBefore = toMessageIdMap(messagesBeforeJson);
+    const messagesIdMapAfter = toMessageIdMap(messagesAfterJson);
+
+    let changed = false;
+
+    for (const [id, message] of messagesIdMapAfter.entries()) {
+      if (!messagesIdMapBefore.has(id)) {
+        console.log("New message:", id);
+        continue;
+      }
+
+      if (messagesIdMapBefore.get(id) !== message) {
+        console.error("ERROR: Message changed:", id);
+        changed = true;
+      }
+    }
+
+    return changed;
+  } catch (e: unknown) {
+    console.error(`ERROR: Unable to compare files ${beforeFile} and ${afterFile}`, e);
+    throw e;
+  }
+}
+
+function toMessageIdMap(messagesJson: Messages): Map<string, string> {
+  return Object.entries(messagesJson).reduce((map, [id, value]) => {
+    map.set(id, value.message);
+    return map;
+  }, new Map<string, string>());
+}
+
+const rootDir = path.join(__dirname, "..", "..");
+const baseBranchRootDir = path.join(rootDir, "base");
+
+const files = findAllLocaleFiles(rootDir);
+
+console.log("Detected valid English locale files:", files);
+
+let changedFiles = false;
+
+for (const file of files) {
+  const baseBranchFile = path.join(baseBranchRootDir, file);
+  if (!fs.existsSync(baseBranchFile)) {
+    console.error("ERROR: File not found in base branch:", file);
+    continue;
+  }
+
+  const changed = compareMessagesJson(baseBranchFile, path.join(rootDir, file));
+  changedFiles ||= changed;
+}
+
+if (changedFiles) {
+  console.error(
+    "ERROR: Incompatible Crowdin locale files. " +
+      "All messages in messages.json locale files needs to be immutable and cannot be updated. " +
+      "If a message needs to be changed, create a new message id and update your code to use it instead.",
+  );
+  process.exit(1);
+}
diff --git a/scripts/tsconfig.json b/scripts/tsconfig.json
new file mode 100644
index 0000000000..018fb13393
--- /dev/null
+++ b/scripts/tsconfig.json
@@ -0,0 +1,9 @@
+{
+  "extends": "../libs/shared/tsconfig",
+  "compilerOptions": {
+    "outDir": "dist",
+    "module": "NodeNext",
+    "target": "ESNext"
+  },
+  "include": ["*.ts"]
+}
diff --git a/tsconfig.eslint.json b/tsconfig.eslint.json
index 23696d3594..f8ab18b498 100644
--- a/tsconfig.eslint.json
+++ b/tsconfig.eslint.json
@@ -42,6 +42,6 @@
       }
     ]
   },
-  "include": ["apps/**/*", "libs/**/*", "bitwarden_license/**/*"],
-  "exclude": ["**/build"]
+  "include": ["apps/**/*", "libs/**/*", "bitwarden_license/**/*", "scripts/**/*"],
+  "exclude": ["**/build", "**/dist"]
 }