diff --git a/test/common/watch.js b/test/common/watch.js
new file mode 100644
index 00000000000000..068790780e1470
--- /dev/null
+++ b/test/common/watch.js
@@ -0,0 +1,16 @@
+'use strict';
+const common = require('./index.js');
+
+exports.skipIfNoWatchModeSignals = function() {
+  if (common.isWindows) {
+    common.skip('no signals on Windows');
+  }
+
+  if (common.isIBMi) {
+    common.skip('IBMi does not support `fs.watch()`');
+  }
+
+  if (common.isAIX) {
+    common.skip('folder watch capability is limited in AIX.');
+  }
+};
diff --git a/test/fixtures/kill-signal-for-watch.js b/test/fixtures/kill-signal-for-watch.js
new file mode 100644
index 00000000000000..bfa67a63a65db0
--- /dev/null
+++ b/test/fixtures/kill-signal-for-watch.js
@@ -0,0 +1,4 @@
+process.on('SIGTERM', () => { console.log('__SIGTERM received__'); process.exit(); });
+process.on('SIGINT', () => { console.log('__SIGINT received__'); process.exit(); });
+process.send('script ready');
+setTimeout(() => {}, 100_000);
diff --git a/test/parallel/test-runner-watch-mode-kill-signal.mjs b/test/parallel/test-runner-watch-mode-kill-signal.mjs
deleted file mode 100644
index d59f4522fadc7f..00000000000000
--- a/test/parallel/test-runner-watch-mode-kill-signal.mjs
+++ /dev/null
@@ -1,131 +0,0 @@
-import * as common from '../common/index.mjs';
-import { describe, it, beforeEach } from 'node:test';
-import assert from 'node:assert';
-import { spawn } from 'node:child_process';
-import { writeFileSync } from 'node:fs';
-import tmpdir from '../common/tmpdir.js';
-
-if (common.isWindows) {
-  common.skip('no signals on Windows');
-}
-
-if (common.isIBMi) {
-  common.skip('IBMi does not support `fs.watch()`');
-}
-
-if (common.isAIX) {
-  common.skip('folder watch capability is limited in AIX.');
-}
-
-const indexContents = `
-  process.on('SIGTERM', () => { console.log('__SIGTERM received__'); process.exit(); });
-  process.on('SIGINT', () => { console.log('__SIGINT received__'); process.exit(); });
-  process.send('script ready');
-  setTimeout(() => {}, 100_000);
-`;
-
-let indexPath = '';
-
-function refresh() {
-  tmpdir.refresh();
-  indexPath = tmpdir.resolve('index.js');
-  writeFileSync(indexPath, indexContents);
-}
-
-describe('test runner watch mode with --watch-kill-signal', () => {
-  beforeEach(refresh);
-
-  it('defaults to SIGTERM', async () => {
-    const child = spawn(
-      process.execPath,
-      ['--watch', indexPath],
-      {
-        cwd: tmpdir.path,
-        stdio: ['pipe', 'pipe', 'pipe', 'ipc'],
-      }
-    );
-
-    let stdout = '';
-    child.stdout.on('data', (data) => {
-      stdout += `${data}`;
-      if (/__(SIGINT|SIGTERM) received__/.test(stdout)) {
-        child.kill();
-      }
-    });
-
-    child.on('message', (msg) => {
-      if (msg === 'script ready') {
-        writeFileSync(indexPath, indexContents);
-      }
-    });
-
-    await new Promise((resolve) =>
-      child.on('exit', () => {
-        resolve();
-      })
-    );
-
-    assert.match(stdout, /__SIGTERM received__/);
-    assert.doesNotMatch(stdout, /__SIGINT received__/);
-  });
-
-  it('can be overridden (to SIGINT)', async () => {
-    const child = spawn(
-      process.execPath,
-      ['--watch', '--watch-kill-signal', 'SIGINT', indexPath],
-      {
-        cwd: tmpdir.path,
-        stdio: ['pipe', 'pipe', 'pipe', 'ipc'],
-      }
-    );
-
-    let stdout = '';
-    child.stdout.on('data', (data) => {
-      stdout += `${data}`;
-      if (/__(SIGINT|SIGTERM) received__/.test(stdout)) {
-        child.kill();
-      }
-    });
-
-    child.on('message', (msg) => {
-      if (msg === 'script ready') {
-        writeFileSync(indexPath, indexContents);
-      }
-    });
-
-    await new Promise((resolve) =>
-      child.on('exit', () => {
-        resolve();
-      })
-    );
-
-    assert.match(stdout, /__SIGINT received__/);
-    assert.doesNotMatch(stdout, /__SIGTERM received__/);
-  });
-
-  it('errors if an invalid signal is provided', async () => {
-    const currentRun = Promise.withResolvers();
-    const child = spawn(
-      process.execPath,
-      ['--watch', '--watch-kill-signal', 'invalid_signal', indexPath],
-      {
-        cwd: tmpdir.path,
-      }
-    );
-    let stdout = '';
-
-    child.stderr.on('data', (data) => {
-      stdout += data.toString();
-      currentRun.resolve();
-    });
-
-    await currentRun.promise;
-
-    assert.match(
-      stdout,
-      new RegExp(
-        /TypeError \[ERR_UNKNOWN_SIGNAL\]: Unknown signal: invalid_signal/
-      )
-    );
-  });
-});
diff --git a/test/parallel/test-watch-mode-kill-signal-default.mjs b/test/parallel/test-watch-mode-kill-signal-default.mjs
new file mode 100644
index 00000000000000..c3b2331e367ebb
--- /dev/null
+++ b/test/parallel/test-watch-mode-kill-signal-default.mjs
@@ -0,0 +1,45 @@
+// Test that the kill signal sent by --watch defaults to SIGTERM.
+
+import '../common/index.mjs';
+import assert from 'node:assert';
+import { writeFileSync } from 'node:fs';
+import { spawn } from 'node:child_process';
+import { once } from 'node:events';
+import tmpdir from '../common/tmpdir.js';
+import fixtures from '../common/fixtures.js';
+import { skipIfNoWatchModeSignals } from '../common/watch.js';
+
+skipIfNoWatchModeSignals();
+
+tmpdir.refresh();
+const indexPath = tmpdir.resolve('kill-signal-for-watch.js');
+const indexContents = fixtures.readSync('kill-signal-for-watch.js', 'utf8');
+writeFileSync(indexPath, indexContents);
+
+const child = spawn(
+  process.execPath,
+  ['--watch', indexPath],
+  {
+    cwd: tmpdir.path,
+    stdio: ['inherit', 'pipe', 'inherit', 'ipc'],
+  }
+);
+
+let stdout = '';
+child.stdout.on('data', (data) => {
+  stdout += `${data}`;
+  if (/__(SIGINT|SIGTERM) received__/.test(stdout)) {
+    child.kill();
+  }
+});
+
+child.on('message', (msg) => {
+  if (msg === 'script ready') {
+    writeFileSync(indexPath, indexContents);
+  }
+});
+
+await once(child, 'exit');
+
+assert.match(stdout, /__SIGTERM received__/);
+assert.doesNotMatch(stdout, /__SIGINT received__/);
diff --git a/test/parallel/test-watch-mode-kill-signal-invalid.mjs b/test/parallel/test-watch-mode-kill-signal-invalid.mjs
new file mode 100644
index 00000000000000..e2f32ba978e210
--- /dev/null
+++ b/test/parallel/test-watch-mode-kill-signal-invalid.mjs
@@ -0,0 +1,39 @@
+// Test that --watch-kill-signal errors when an invalid kill signal is provided.
+
+import '../common/index.mjs';
+import assert from 'node:assert';
+import { writeFileSync } from 'node:fs';
+import { spawn } from 'node:child_process';
+import tmpdir from '../common/tmpdir.js';
+import fixtures from '../common/fixtures.js';
+import { skipIfNoWatchModeSignals } from '../common/watch.js';
+
+skipIfNoWatchModeSignals();
+
+tmpdir.refresh();
+const indexPath = tmpdir.resolve('kill-signal-for-watch.js');
+const indexContents = fixtures.readSync('kill-signal-for-watch.js', 'utf8');
+writeFileSync(indexPath, indexContents);
+
+const currentRun = Promise.withResolvers();
+const child = spawn(
+  process.execPath,
+  ['--watch', '--watch-kill-signal', 'invalid_signal', indexPath],
+  {
+    cwd: tmpdir.path,
+    stdio: ['inherit', 'inherit', 'pipe'],
+  }
+);
+let stderr = '';
+
+child.stderr.on('data', (data) => {
+  stderr += data.toString();
+  currentRun.resolve();
+});
+
+await currentRun.promise;
+
+assert.match(
+  stderr,
+  /TypeError \[ERR_UNKNOWN_SIGNAL\]: Unknown signal: invalid_signal/
+);
diff --git a/test/parallel/test-watch-mode-kill-signal-override.mjs b/test/parallel/test-watch-mode-kill-signal-override.mjs
new file mode 100644
index 00000000000000..cc9e1219bc616e
--- /dev/null
+++ b/test/parallel/test-watch-mode-kill-signal-override.mjs
@@ -0,0 +1,46 @@
+// Test that the kill signal sent by --watch can be overridden to SIGINT
+// by using --watch-kill-signal.
+
+import '../common/index.mjs';
+import assert from 'node:assert';
+import { writeFileSync } from 'node:fs';
+import { spawn } from 'node:child_process';
+import { once } from 'node:events';
+import tmpdir from '../common/tmpdir.js';
+import fixtures from '../common/fixtures.js';
+import { skipIfNoWatchModeSignals } from '../common/watch.js';
+
+skipIfNoWatchModeSignals();
+
+tmpdir.refresh();
+const indexPath = tmpdir.resolve('kill-signal-for-watch.js');
+const indexContents = fixtures.readSync('kill-signal-for-watch.js', 'utf8');
+writeFileSync(indexPath, indexContents);
+
+const child = spawn(
+  process.execPath,
+  ['--watch', '--watch-kill-signal', 'SIGINT', indexPath],
+  {
+    cwd: tmpdir.path,
+    stdio: ['inherit', 'pipe', 'inherit', 'ipc'],
+  }
+);
+
+let stdout = '';
+child.stdout.on('data', (data) => {
+  stdout += `${data}`;
+  if (/__(SIGINT|SIGTERM) received__/.test(stdout)) {
+    child.kill();
+  }
+});
+
+child.on('message', (msg) => {
+  if (msg === 'script ready') {
+    writeFileSync(indexPath, indexContents);
+  }
+});
+
+await once(child, 'exit');
+
+assert.match(stdout, /__SIGINT received__/);
+assert.doesNotMatch(stdout, /__SIGTERM received__/);