diff --git a/lib/child_process.js b/lib/child_process.js
index 62c552d567eaad..7f6621734b108c 100644
--- a/lib/child_process.js
+++ b/lib/child_process.js
@@ -690,7 +690,9 @@ function abortChildProcess(child, killSignal) {
 function spawn(file, args, options) {
   options = normalizeSpawnArguments(file, args, options);
   validateTimeout(options.timeout);
-  validateAbortSignal(options.signal, 'options.signal');
+  if (options.signal !== undefined)
+    validateAbortSignal(options.signal, 'options.signal');
+
   const killSignal = sanitizeKillSignal(options.killSignal);
   const child = new ChildProcess();
 
diff --git a/lib/events.js b/lib/events.js
index ef8090e57778e7..64273507efd047 100644
--- a/lib/events.js
+++ b/lib/events.js
@@ -808,7 +808,8 @@ function getEventListeners(emitterOrTarget, type) {
  */
 async function once(emitter, name, options = {}) {
   const signal = options?.signal;
-  validateAbortSignal(signal, 'options.signal');
+  if (signal !== undefined)
+    validateAbortSignal(signal, 'options.signal');
   if (signal?.aborted)
     throw new AbortError();
   return new Promise((resolve, reject) => {
@@ -886,7 +887,8 @@ function eventTargetAgnosticAddListener(emitter, name, listener, flags) {
  */
 function on(emitter, event, options) {
   const signal = options?.signal;
-  validateAbortSignal(signal, 'options.signal');
+  if (signal !== undefined)
+    validateAbortSignal(signal, 'options.signal');
   if (signal?.aborted)
     throw new AbortError();
 
diff --git a/lib/internal/fs/promises.js b/lib/internal/fs/promises.js
index b9c3b7cb407159..cf77e9ad7f2c4a 100644
--- a/lib/internal/fs/promises.js
+++ b/lib/internal/fs/promises.js
@@ -813,7 +813,8 @@ async function writeFile(path, data, options) {
     data = Buffer.from(data, options.encoding || 'utf8');
   }
 
-  validateAbortSignal(options.signal);
+  if (options.signal !== undefined)
+    validateAbortSignal(options.signal);
   if (path instanceof FileHandle)
     return writeFileHandle(path, data, options.signal, options.encoding);
 
diff --git a/lib/internal/fs/watchers.js b/lib/internal/fs/watchers.js
index b45af42d12ff7d..37fbc06a74c008 100644
--- a/lib/internal/fs/watchers.js
+++ b/lib/internal/fs/watchers.js
@@ -308,7 +308,8 @@ async function* watch(filename, options = {}) {
 
   validateBoolean(persistent, 'options.persistent');
   validateBoolean(recursive, 'options.recursive');
-  validateAbortSignal(signal, 'options.signal');
+  if (signal !== undefined)
+    validateAbortSignal(signal, 'options.signal');
 
   if (encoding && !isEncoding(encoding)) {
     const reason = 'is invalid encoding';
diff --git a/lib/internal/streams/end-of-stream.js b/lib/internal/streams/end-of-stream.js
index c224b44eac6631..da8fe36fd7514a 100644
--- a/lib/internal/streams/end-of-stream.js
+++ b/lib/internal/streams/end-of-stream.js
@@ -45,7 +45,8 @@ function eos(stream, options, callback) {
     validateObject(options, 'options');
   }
   validateFunction(callback, 'callback');
-  validateAbortSignal(options.signal, 'options.signal');
+  if (options.signal !== undefined)
+    validateAbortSignal(options.signal, 'options.signal');
 
   callback = once(callback);
 
diff --git a/lib/internal/streams/pipeline.js b/lib/internal/streams/pipeline.js
index 8dc4e5792c47d8..85a5e8025a05ee 100644
--- a/lib/internal/streams/pipeline.js
+++ b/lib/internal/streams/pipeline.js
@@ -182,7 +182,8 @@ function pipelineImpl(streams, callback, opts) {
   const signal = ac.signal;
   const outerSignal = opts?.signal;
 
-  validateAbortSignal(outerSignal, 'options.signal');
+  if (outerSignal !== undefined)
+    validateAbortSignal(outerSignal, 'options.signal');
 
   function abort() {
     finishImpl(new AbortError());
diff --git a/lib/internal/validators.js b/lib/internal/validators.js
index 81329160f07323..a9d884f0bf078d 100644
--- a/lib/internal/validators.js
+++ b/lib/internal/validators.js
@@ -224,10 +224,8 @@ const validateCallback = hideStackFrames((callback) => {
 });
 
 const validateAbortSignal = hideStackFrames((signal, name) => {
-  if (signal !== undefined &&
-      (signal === null ||
-       typeof signal !== 'object' ||
-       !('aborted' in signal))) {
+  if (signal === null || typeof signal !== 'object' ||
+      !('aborted' in signal)) {
     throw new ERR_INVALID_ARG_TYPE(name, 'AbortSignal', signal);
   }
 });
diff --git a/lib/timers/promises.js b/lib/timers/promises.js
index 162f465da29dec..52314c3e81f949 100644
--- a/lib/timers/promises.js
+++ b/lib/timers/promises.js
@@ -41,10 +41,12 @@ function setTimeout(after, value, options = {}) {
         options));
   }
   const { signal, ref = true } = options;
-  try {
-    validateAbortSignal(signal, 'options.signal');
-  } catch (err) {
-    return PromiseReject(err);
+  if (signal !== undefined) {
+    try {
+      validateAbortSignal(signal, 'options.signal');
+    } catch (err) {
+      return PromiseReject(err);
+    }
   }
   if (typeof ref !== 'boolean') {
     return PromiseReject(
@@ -85,10 +87,12 @@ function setImmediate(value, options = {}) {
         options));
   }
   const { signal, ref = true } = options;
-  try {
-    validateAbortSignal(signal, 'options.signal');
-  } catch (err) {
-    return PromiseReject(err);
+  if (signal !== undefined) {
+    try {
+      validateAbortSignal(signal, 'options.signal');
+    } catch (err) {
+      return PromiseReject(err);
+    }
   }
   if (typeof ref !== 'boolean') {
     return PromiseReject(
@@ -123,7 +127,8 @@ function setImmediate(value, options = {}) {
 async function* setInterval(after, value, options = {}) {
   validateObject(options, 'options');
   const { signal, ref = true } = options;
-  validateAbortSignal(signal, 'options.signal');
+  if (signal !== undefined)
+    validateAbortSignal(signal, 'options.signal');
   validateBoolean(ref, 'options.ref');
 
   if (signal?.aborted)