diff --git a/e2e/release/src/release-publishable-libraries-ts-solution.test.ts b/e2e/release/src/release-publishable-libraries-ts-solution.test.ts
index c63fe882ac..c79f63fe90 100644
--- a/e2e/release/src/release-publishable-libraries-ts-solution.test.ts
+++ b/e2e/release/src/release-publishable-libraries-ts-solution.test.ts
@@ -168,8 +168,8 @@ describe('release publishable libraries in workspace with ts solution setup', ()
       📦  @proj/{project-name}@0.0.3
       === Tarball Contents ===
       XXB README.md
+      XXB dist/index.d.ts
       XXB dist/index.esm.css
-      XXB dist/index.esm.d.ts
       XXB dist/index.esm.js
       XXX.XXX kb dist/README.md
       XXB dist/src/index.d.ts
diff --git a/e2e/release/src/release-publishable-libraries.test.ts b/e2e/release/src/release-publishable-libraries.test.ts
index 888af9994c..dacfb67098 100644
--- a/e2e/release/src/release-publishable-libraries.test.ts
+++ b/e2e/release/src/release-publishable-libraries.test.ts
@@ -170,8 +170,8 @@ describe('release publishable libraries', () => {
       📦  @proj/{project-name}@0.0.3
       === Tarball Contents ===
       XXX.XXX kb README.md
+      XXB index.d.ts
       XXB index.esm.css
-      XXB index.esm.d.ts
       XXB index.esm.js
       XXXB package.json
       XXB src/index.d.ts
diff --git a/e2e/rollup/src/rollup-legacy.test.ts b/e2e/rollup/src/rollup-legacy.test.ts
index d93e98580e..b7fec5ec9f 100644
--- a/e2e/rollup/src/rollup-legacy.test.ts
+++ b/e2e/rollup/src/rollup-legacy.test.ts
@@ -41,13 +41,13 @@ describe('Rollup Plugin', () => {
     );
     rmDist();
     runCLI(`build ${myPkg} --format=cjs,esm --generateExportsField`);
-    checkFilesExist(`dist/libs/${myPkg}/index.cjs.d.ts`);
+    checkFilesExist(`dist/libs/${myPkg}/index.d.ts`);
     expect(readJson(`dist/libs/${myPkg}/package.json`).exports).toEqual({
       '.': {
         module: './index.esm.js',
         import: './index.cjs.mjs',
         default: './index.cjs.js',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       },
       './package.json': './package.json',
     });
@@ -106,7 +106,7 @@ describe('Rollup Plugin', () => {
 
     checkFilesExist(`dist/libs/${myPkg}/index.esm.js`);
     checkFilesExist(`dist/libs/${myPkg}/index.cjs.js`);
-    checkFilesExist(`dist/libs/${myPkg}/index.cjs.d.ts`);
+    checkFilesExist(`dist/libs/${myPkg}/index.d.ts`);
     checkFilesExist(`dist/libs/${myPkg}/foo.esm.js`);
     checkFilesExist(`dist/libs/${myPkg}/foo.cjs.js`);
     checkFilesExist(`dist/libs/${myPkg}/bar.esm.js`);
@@ -117,19 +117,19 @@ describe('Rollup Plugin', () => {
         module: './index.esm.js',
         import: './index.cjs.mjs',
         default: './index.cjs.js',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       },
       './bar': {
         module: './bar.esm.js',
         import: './bar.cjs.mjs',
         default: './bar.cjs.js',
-        types: './bar.esm.d.ts',
+        types: './bar.d.ts',
       },
       './foo': {
         module: './foo.esm.js',
         import: './foo.cjs.mjs',
         default: './foo.cjs.js',
-        types: './foo.esm.d.ts',
+        types: './foo.d.ts',
       },
     });
   });
diff --git a/e2e/rollup/src/rollup.test.ts b/e2e/rollup/src/rollup.test.ts
index bce8c2ca4c..5411baae18 100644
--- a/e2e/rollup/src/rollup.test.ts
+++ b/e2e/rollup/src/rollup.test.ts
@@ -43,13 +43,13 @@ describe('Rollup Plugin', () => {
     );
     rmDist();
     runCLI(`build ${myPkg}`);
-    checkFilesExist(`dist/libs/${myPkg}/index.cjs.d.ts`);
+    checkFilesExist(`dist/libs/${myPkg}/index.d.ts`);
     expect(readJson(`dist/libs/${myPkg}/package.json`).exports).toEqual({
       '.': {
         module: './index.esm.js',
         import: './index.cjs.mjs',
         default: './index.cjs.js',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       },
       './package.json': './package.json',
     });
@@ -139,7 +139,7 @@ describe('Rollup Plugin', () => {
     checkFilesExist(`dist/libs/${myPkg}/index.esm.js.map`);
     checkFilesExist(`dist/libs/${myPkg}/index.cjs.js`);
     checkFilesExist(`dist/libs/${myPkg}/index.cjs.js.map`);
-    checkFilesExist(`dist/libs/${myPkg}/index.cjs.d.ts`);
+    checkFilesExist(`dist/libs/${myPkg}/index.d.ts`);
     checkFilesExist(`dist/libs/${myPkg}/foo.esm.js`);
     checkFilesExist(`dist/libs/${myPkg}/foo.esm.js.map`);
     checkFilesExist(`dist/libs/${myPkg}/foo.cjs.js`);
@@ -154,19 +154,19 @@ describe('Rollup Plugin', () => {
         module: './index.esm.js',
         import: './index.cjs.mjs',
         default: './index.cjs.js',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       },
       './bar': {
         module: './bar.esm.js',
         import: './bar.cjs.mjs',
         default: './bar.cjs.js',
-        types: './bar.esm.d.ts',
+        types: './bar.d.ts',
       },
       './foo': {
         module: './foo.esm.js',
         import: './foo.cjs.mjs',
         default: './foo.cjs.js',
-        types: './foo.esm.d.ts',
+        types: './foo.d.ts',
       },
     });
   });
diff --git a/packages/js/src/plugins/rollup/type-definitions.spec.ts b/packages/js/src/plugins/rollup/type-definitions.spec.ts
new file mode 100644
index 0000000000..c135071da4
--- /dev/null
+++ b/packages/js/src/plugins/rollup/type-definitions.spec.ts
@@ -0,0 +1,71 @@
+import { typeDefinitions } from './type-definitions';
+describe('typeDefinitions', () => {
+  it('should emit correct .d.ts filenames for various file formats', () => {
+    const mockBundle = {
+      'index.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.js',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+      'index1.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.cjs',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+      'index2.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.mjs',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+      'index3.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.cjs.js',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+      'index4.js': {
+        type: 'chunk',
+        isEntry: true,
+        fileName: 'index.mjs.js',
+        facadeModuleId: '/project/src/index.ts',
+        exports: ['default', 'namedExport1', 'namedExport2'],
+      },
+    };
+
+    const mockOpts = {}; // Can be left empty for this scenario
+
+    const mockEmitFile = jest.fn();
+
+    const plugin = typeDefinitions({ projectRoot: '/project' });
+
+    // Simulate the `this` context of a Rollup plugin
+    const mockContext = {
+      emitFile: mockEmitFile,
+    };
+
+    // Run the plugin's `generateBundle` function
+    (async function testPlugin() {
+      await plugin.generateBundle.call(mockContext, mockOpts, mockBundle);
+
+      // Verify the correct .d.ts filenames are generated for different file formats
+      const expectedFileNames = [
+        'index.d.ts', // from index.js
+        'index.d.ts', // from index.cjs
+        'index.d.ts', // from index.mjs
+        'index.d.ts', // from index.cjs.js
+        'index.d.ts', // from index.mjs.js
+      ];
+
+      mockEmitFile.mock.calls.forEach(([{ fileName }], index) => {
+        expect(fileName).toBe(expectedFileNames[index]);
+      });
+    })();
+  });
+});
diff --git a/packages/js/src/plugins/rollup/type-definitions.ts b/packages/js/src/plugins/rollup/type-definitions.ts
index f82ddf505b..a2a2a604f6 100644
--- a/packages/js/src/plugins/rollup/type-definitions.ts
+++ b/packages/js/src/plugins/rollup/type-definitions.ts
@@ -38,7 +38,14 @@ export function typeDefinitions(options: { projectRoot: string }) {
           /\.[cm]?[jt]sx?$/,
           ''
         );
-        const dtsFileName = file.fileName.replace(/\.[cm]?js$/, '.d.ts');
+
+        // Replace various JavaScript file extensions (e.g., .js, .cjs, .mjs, .cjs.js, .mjs.js) with .d.ts for generating type definition file names.
+        // This regex matches the pattern used in packages/rollup/src/plugins/package-json/update-package-json.ts
+        const dtsFileName = file.fileName.replace(
+          /(\.cjs|\.mjs|\.esm\.js|\.cjs\.js|\.mjs\.js|\.js)$/,
+          '.d.ts'
+        );
+
         const relativeSourceDtsName = JSON.stringify('./' + entrySourceDtsName);
         const dtsFileSource = hasDefaultExport
           ? stripIndents`
diff --git a/packages/rollup/src/plugins/package-json/update-package-json.spec.ts b/packages/rollup/src/plugins/package-json/update-package-json.spec.ts
index c10f92a926..c617498aab 100644
--- a/packages/rollup/src/plugins/package-json/update-package-json.spec.ts
+++ b/packages/rollup/src/plugins/package-json/update-package-json.spec.ts
@@ -32,13 +32,13 @@ describe('updatePackageJson', () => {
           './package.json': './package.json',
           '.': {
             import: './index.esm.js',
-            types: './index.esm.d.ts',
+            types: './index.d.ts',
           },
         },
         main: './index.esm.js',
         module: './index.esm.js',
         type: 'module',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       });
 
       spy.mockRestore();
@@ -63,7 +63,7 @@ describe('updatePackageJson', () => {
         },
         main: './index.cjs.js',
         type: 'commonjs',
-        types: './index.cjs.d.ts',
+        types: './index.d.ts',
       });
 
       spy.mockRestore();
@@ -88,12 +88,12 @@ describe('updatePackageJson', () => {
             module: './index.esm.js',
             import: './index.cjs.mjs',
             default: './index.cjs.js',
-            types: './index.esm.d.ts',
+            types: './index.d.ts',
           },
         },
         main: './index.cjs.js',
         module: './index.esm.js',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       });
 
       spy.mockRestore();
@@ -123,7 +123,7 @@ describe('updatePackageJson', () => {
           './package.json': './package.json',
           '.': {
             import: './index.esm.js',
-            types: './index.esm.d.ts',
+            types: './index.d.ts',
           },
           './foo': {
             import: './some/custom/path/foo.esm.js',
@@ -133,7 +133,7 @@ describe('updatePackageJson', () => {
         main: './index.esm.js',
         module: './index.esm.js',
         type: 'module',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       });
 
       spy.mockRestore();
@@ -156,7 +156,7 @@ describe('updatePackageJson', () => {
         main: './index.esm.js',
         module: './index.esm.js',
         type: 'module',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       });
 
       spy.mockRestore();
@@ -176,7 +176,7 @@ describe('updatePackageJson', () => {
       expect(utils.writeJsonFile).toHaveBeenCalledWith(expect.anything(), {
         main: './index.cjs.js',
         type: 'commonjs',
-        types: './index.cjs.d.ts',
+        types: './index.d.ts',
       });
 
       spy.mockRestore();
@@ -196,7 +196,7 @@ describe('updatePackageJson', () => {
       expect(utils.writeJsonFile).toHaveBeenCalledWith(expect.anything(), {
         main: './index.cjs.js',
         module: './index.esm.js',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
       });
 
       spy.mockRestore();
@@ -221,7 +221,7 @@ describe('updatePackageJson', () => {
         main: './index.esm.js',
         module: './index.esm.js',
         type: 'module',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
         exports: {
           './foo': './foo.esm.js',
         },
@@ -251,7 +251,7 @@ describe('updatePackageJson', () => {
       expect(utils.writeJsonFile).toHaveBeenCalledWith(expect.anything(), {
         main: './index.esm.js',
         module: './index.esm.js',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
         exports: {
           './foo': './foo.esm.js',
         },
@@ -279,7 +279,7 @@ describe('updatePackageJson', () => {
         main: './index.esm.js',
         module: './index.esm.js',
         type: 'module',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
         exports: {
           './foo': './foo.esm.js',
         },
@@ -308,7 +308,7 @@ describe('updatePackageJson', () => {
         main: './index.esm.js',
         module: './index.esm.js',
         type: 'module',
-        types: './index.esm.d.ts',
+        types: './index.d.ts',
         exports: {
           './foo': './foo.esm.js',
         },
diff --git a/packages/rollup/src/plugins/package-json/update-package-json.ts b/packages/rollup/src/plugins/package-json/update-package-json.ts
index ce5cf85295..bf20c9fcfc 100644
--- a/packages/rollup/src/plugins/package-json/update-package-json.ts
+++ b/packages/rollup/src/plugins/package-json/update-package-json.ts
@@ -16,6 +16,7 @@ export function updatePackageJson(
   },
   packageJson: PackageJson
 ) {
+  const jsFileRegex = /(\.cjs|\.mjs|\.esm\.js|\.cjs\.js|\.mjs\.js|\.js)$/;
   const hasEsmFormat = options.format.includes('esm');
   const hasCjsFormat = options.format.includes('cjs');
 
@@ -46,7 +47,7 @@ export function updatePackageJson(
           // Reserve `module` entry for bundlers to accommodate tree-shaking.
           {
             [hasCjsFormat ? 'module' : 'import']: filePath,
-            types: filePath.replace(/\.js$/, '.d.ts'),
+            types: filePath.replace(jsFileRegex, '.d.ts'),
           };
       }
     }
@@ -110,9 +111,9 @@ export function updatePackageJson(
   }
 
   if (packageJson.module) {
-    packageJson.types ??= packageJson.module.replace(/\.js$/, '.d.ts');
+    packageJson.types ??= packageJson.module.replace(jsFileRegex, '.d.ts');
   } else {
-    packageJson.types ??= packageJson.main.replace(/\.js$/, '.d.ts');
+    packageJson.types ??= packageJson.main.replace(jsFileRegex, '.d.ts');
   }
 
   writeJsonFile(