diff --git a/packages/schematics/angular/web-worker/index.ts b/packages/schematics/angular/web-worker/index.ts
index 45e1f39ad34c..e37754aa48e9 100644
--- a/packages/schematics/angular/web-worker/index.ts
+++ b/packages/schematics/angular/web-worker/index.ts
@@ -41,8 +41,8 @@ function addSnippet(options: WebWorkerOptions): Rule {
     const siblingModules = host
       .getDir(options.path)
       .subfiles // Find all files that start with the same name, are ts files,
-      // and aren't spec or module files.
-      .filter((f) => fileRegExp.test(f) && !/(module|spec|config|routes)\.ts$/.test(f))
+      // and aren't spec, module, declaration, or configuration files (including their server variants).
+      .filter((f) => fileRegExp.test(f) && !/\.(module|spec|config|routes|server|d)\.ts$/.test(f))
       // Sort alphabetically for consistency.
       .sort();
 
diff --git a/packages/schematics/angular/web-worker/index_spec.ts b/packages/schematics/angular/web-worker/index_spec.ts
index a922a6d3cee6..4117f06e32e8 100644
--- a/packages/schematics/angular/web-worker/index_spec.ts
+++ b/packages/schematics/angular/web-worker/index_spec.ts
@@ -95,6 +95,36 @@ describe('Web Worker Schematic', () => {
     expect(appComponent).toContain('console.log(`page got message: ${data}`)');
   });
 
+  it('should add snippet to the component file and not a server configuration file', async () => {
+    const serverAppTree = await schematicRunner.runSchematic('server', { project: 'bar' }, appTree);
+    const tree = await schematicRunner.runSchematic('web-worker', defaultOptions, serverAppTree);
+
+    const appComponent = tree.readContent('/projects/bar/src/app/app.ts');
+    expect(appComponent).toContain(`new Worker(new URL('./${defaultOptions.name}.worker`);
+
+    const serverConfig = tree.readContent('/projects/bar/src/app/app.config.server.ts');
+    expect(serverConfig).not.toContain('new Worker');
+  });
+
+  it(`should add snippet to a sibling file whose name ends with 'server'`, async () => {
+    appTree.create('/projects/bar/src/app/observer.ts', 'export class Observer {}\n');
+    const options = { ...defaultOptions, name: 'observer' };
+    const tree = await schematicRunner.runSchematic('web-worker', options, appTree);
+
+    const content = tree.readContent('/projects/bar/src/app/observer.ts');
+    expect(content).toContain(`new Worker(new URL('./observer.worker`);
+  });
+
+  it('should not add snippet to a declaration file', async () => {
+    appTree.create('/projects/bar/src/app/app.d.ts', 'declare const foo: string;\n');
+    const tree = await schematicRunner.runSchematic('web-worker', defaultOptions, appTree);
+
+    expect(tree.readContent('/projects/bar/src/app/app.d.ts')).not.toContain('new Worker');
+    expect(tree.readContent('/projects/bar/src/app/app.ts')).toContain(
+      `new Worker(new URL('./${defaultOptions.name}.worker`,
+    );
+  });
+
   it(`should add 'tsconfig.worker.json' outside of 'src' directory in root app`, async () => {
     const rootAppOptions = { ...appOptions, projectRoot: '', name: 'foo' };
     const workerOptions = { ...defaultOptions, project: 'foo' };