diff --git a/packages/playwright/src/program.ts b/packages/playwright/src/program.ts
index cfe2d471ff..cbe161b59f 100644
--- a/packages/playwright/src/program.ts
+++ b/packages/playwright/src/program.ts
@@ -34,7 +34,7 @@ import { program } from 'playwright-core/lib/cli/program';
 export { program } from 'playwright-core/lib/cli/program';
 import type { ReporterDescription } from '../types/test';
 import { prepareErrorStack } from './reporters/base';
-import { affectedTestFiles, cacheDir } from './transform/compilationCache';
+import { cacheDir } from './transform/compilationCache';
 import { runTestServer } from './runner/testServer';
 
 function addTestCommand(program: Command) {
@@ -102,17 +102,7 @@ function addFindRelatedTestFilesCommand(program: Command) {
   command.description('Returns the list of related tests to the given files');
   command.option('-c, --config <file>', `Configuration file, or a test directory with optional "playwright.config.{m,c}?{js,ts}"`);
   command.action(async (files, options) => {
-    await withRunnerAndMutedWrite(options.config, async (runner, config, configDir) => {
-      const result = await runner.loadAllTests();
-      if (result.status !== 'passed' || !result.suite)
-        return { errors: result.errors };
-
-      const resolvedFiles = (files as string[]).map(file => path.resolve(process.cwd(), file));
-      const override = (config as any)['@playwright/test']?.['cli']?.['find-related-test-files'];
-      if (override)
-        return await override(resolvedFiles, config, configDir, result.suite);
-      return { testFiles: affectedTestFiles(resolvedFiles) };
-    });
+    await withRunnerAndMutedWrite(options.config, runner => runner.findRelatedTestFiles('in-process', files));
   });
 }
 
diff --git a/packages/playwright/src/runner/runner.ts b/packages/playwright/src/runner/runner.ts
index e9df35fd4e..51e902377a 100644
--- a/packages/playwright/src/runner/runner.ts
+++ b/packages/playwright/src/runner/runner.ts
@@ -30,6 +30,7 @@ import { InternalReporter } from '../reporters/internalReporter';
 import { Multiplexer } from '../reporters/multiplexer';
 import type { Suite } from '../common/test';
 import { wrapReporterAsV2 } from '../reporters/reporterV2';
+import { affectedTestFiles } from '../transform/compilationCache';
 
 type ProjectConfigWithFiles = {
   name: string;
@@ -44,6 +45,11 @@ type ConfigListFilesReport = {
   error?: TestError;
 };
 
+export type FindRelatedTestFilesReport = {
+  testFiles: string[];
+  errors?: TestError[];
+};
+
 export class Runner {
   private _config: FullConfigInternal;
 
@@ -144,4 +150,16 @@ export class Runner {
     webServerPluginsForConfig(config).forEach(p => config.plugins.push({ factory: p }));
     return await runUIMode(config, options);
   }
+
+  async findRelatedTestFiles(mode: 'in-process' | 'out-of-process', files: string[]): Promise<FindRelatedTestFilesReport>  {
+    const result = await this.loadAllTests(mode);
+    if (result.status !== 'passed' || !result.suite)
+      return { errors: result.errors, testFiles: [] };
+
+    const resolvedFiles = (files as string[]).map(file => path.resolve(process.cwd(), file));
+    const override = (this._config.config as any)['@playwright/test']?.['cli']?.['find-related-test-files'];
+    if (override)
+      return await override(resolvedFiles, this._config.config, this._config.configDir, result.suite);
+    return { testFiles: affectedTestFiles(resolvedFiles) };
+  }
 }
diff --git a/packages/playwright/src/runner/testServer.ts b/packages/playwright/src/runner/testServer.ts
index 4abe2b122b..805a73ceb8 100644
--- a/packages/playwright/src/runner/testServer.ts
+++ b/packages/playwright/src/runner/testServer.ts
@@ -27,6 +27,8 @@ import { Multiplexer } from '../reporters/multiplexer';
 import { createReporters } from './reporters';
 import { TestRun, createTaskRunnerForList, createTaskRunnerForTestServer } from './tasks';
 import type { ConfigCLIOverrides } from '../common/ipc';
+import { Runner } from './runner';
+import type { FindRelatedTestFilesReport } from './runner';
 
 type PlaywrightTestOptions = {
   headed?: boolean,
@@ -117,6 +119,12 @@ class Dispatcher {
     await this._runTests(params.reporter, params.locations, params.options);
   }
 
+  async findRelatedTestFiles(params:  { files: string[] }): Promise<FindRelatedTestFilesReport> {
+    const config = await this._loadConfig({});
+    const runner = new Runner(config);
+    return runner.findRelatedTestFiles('out-of-process', params.files);
+  }
+
   async stop() {
     await this._stopTests();
   }