diff --git a/doc/api/cli.md b/doc/api/cli.md
index 5ba337276597b9..4043597b4fbafd 100644
--- a/doc/api/cli.md
+++ b/doc/api/cli.md
@@ -949,16 +949,6 @@ added: v12.3.0
 
 Enable experimental WebAssembly module support.
 
-### `--experimental-websocket`
-
-<!-- YAML
-added:
-  - v21.0.0
-  - v20.10.0
--->
-
-Enable experimental [`WebSocket`][] support.
-
 ### `--force-context-aware`
 
 <!-- YAML
@@ -1377,6 +1367,14 @@ added: v16.6.0
 
 Use this flag to disable top-level await in REPL.
 
+### `--no-experimental-websocket`
+
+<!-- YAML
+added: REPLACEME
+-->
+
+Use this flag to disable experimental [`WebSocket`][] support.
+
 ### `--no-extra-info-on-fatal-exception`
 
 <!-- YAML
@@ -2511,7 +2509,6 @@ Node.js options that are allowed are:
 * `--experimental-vm-modules`
 * `--experimental-wasi-unstable-preview1`
 * `--experimental-wasm-modules`
-* `--experimental-websocket`
 * `--force-context-aware`
 * `--force-fips`
 * `--force-node-api-uncaught-exceptions-policy`
@@ -2536,6 +2533,7 @@ Node.js options that are allowed are:
 * `--no-experimental-global-navigator`
 * `--no-experimental-global-webcrypto`
 * `--no-experimental-repl-await`
+* `--no-experimental-websocket`
 * `--no-extra-info-on-fatal-exception`
 * `--no-force-async-hooks-checks`
 * `--no-global-search-paths`
diff --git a/doc/api/globals.md b/doc/api/globals.md
index e8a46b67d6007d..ef04062ddfc2a5 100644
--- a/doc/api/globals.md
+++ b/doc/api/globals.md
@@ -1097,12 +1097,16 @@ The object that acts as the namespace for all W3C
 added:
   - v21.0.0
   - v20.10.0
+changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/51594
+    description: No longer behind `--experimental-websocket` CLI flag.
 -->
 
 > Stability: 1 - Experimental.
 
-A browser-compatible implementation of [`WebSocket`][]. Enable this API
-with the [`--experimental-websocket`][] CLI flag.
+A browser-compatible implementation of [`WebSocket`][]. Disable this API
+with the [`--no-experimental-websocket`][] CLI flag.
 
 ## Class: `WritableStream`
 
@@ -1139,10 +1143,10 @@ A browser-compatible implementation of [`WritableStreamDefaultWriter`][].
 [Navigator API]: https://html.spec.whatwg.org/multipage/system-state.html#the-navigator-object
 [RFC 5646]: https://www.rfc-editor.org/rfc/rfc5646.txt
 [Web Crypto API]: webcrypto.md
-[`--experimental-websocket`]: cli.md#--experimental-websocket
 [`--no-experimental-global-customevent`]: cli.md#--no-experimental-global-customevent
 [`--no-experimental-global-navigator`]: cli.md#--no-experimental-global-navigator
 [`--no-experimental-global-webcrypto`]: cli.md#--no-experimental-global-webcrypto
+[`--no-experimental-websocket`]: cli.md#--no-experimental-websocket
 [`AbortController`]: https://developer.mozilla.org/en-US/docs/Web/API/AbortController
 [`ByteLengthQueuingStrategy`]: webstreams.md#class-bytelengthqueuingstrategy
 [`CompressionStream`]: webstreams.md#class-compressionstream
diff --git a/doc/node.1 b/doc/node.1
index 2966c14e1c3f5e..26a979363f8d5b 100644
--- a/doc/node.1
+++ b/doc/node.1
@@ -186,12 +186,12 @@ Use this flag to enable ShadowRealm support.
 .It Fl -experimental-test-coverage
 Enable code coverage in the test runner.
 .
-.It Fl -experimental-websocket
-Enable experimental support for the WebSocket API.
-.
 .It Fl -no-experimental-fetch
 Disable experimental support for the Fetch API.
 .
+.It Fl -no-experimental-websocket
+Disable experimental support for the WebSocket API.
+.
 .It Fl -no-experimental-global-customevent
 Disable exposition of the CustomEvent on the global scope.
 .
diff --git a/lib/internal/bootstrap/web/exposed-window-or-worker.js b/lib/internal/bootstrap/web/exposed-window-or-worker.js
index fe38603cdab5cc..2459bee85bb8b0 100644
--- a/lib/internal/bootstrap/web/exposed-window-or-worker.js
+++ b/lib/internal/bootstrap/web/exposed-window-or-worker.js
@@ -92,6 +92,9 @@ exposeLazyInterfaces(globalThis, 'internal/deps/undici/undici', [
   'FormData', 'Headers', 'Request', 'Response',
 ]);
 
+// https://websockets.spec.whatwg.org/
+exposeLazyInterfaces(globalThis, 'internal/deps/undici/undici', ['WebSocket']);
+
 // The WebAssembly Web API which relies on Response.
 // https:// webassembly.github.io/spec/web-api/#streaming-modules
 internalBinding('wasm_web_api').setImplementation((streamState, source) => {
diff --git a/lib/internal/process/pre_execution.js b/lib/internal/process/pre_execution.js
index eae3859cc5bc83..b7cf9390c9845c 100644
--- a/lib/internal/process/pre_execution.js
+++ b/lib/internal/process/pre_execution.js
@@ -315,8 +315,8 @@ function setupUndici() {
     delete globalThis.Response;
   }
 
-  if (!getEmbedderOptions().noBrowserGlobals && getOptionValue('--experimental-websocket')) {
-    exposeLazyInterfaces(globalThis, 'internal/deps/undici/undici', ['WebSocket']);
+  if (getOptionValue('--no-experimental-websocket')) {
+    delete globalThis.WebSocket;
   }
 }
 
diff --git a/src/node_options.h b/src/node_options.h
index 915151b7dc2904..a0b56ebacb436c 100644
--- a/src/node_options.h
+++ b/src/node_options.h
@@ -108,7 +108,7 @@ class EnvironmentOptions : public Options {
   std::string dns_result_order;
   bool enable_source_maps = false;
   bool experimental_fetch = true;
-  bool experimental_websocket = false;
+  bool experimental_websocket = true;
   bool experimental_global_customevent = true;
   bool experimental_global_navigator = true;
   bool experimental_global_web_crypto = true;
diff --git a/test/parallel/test-websocket-disabled.js b/test/parallel/test-websocket-disabled.js
new file mode 100644
index 00000000000000..4d72294367718b
--- /dev/null
+++ b/test/parallel/test-websocket-disabled.js
@@ -0,0 +1,7 @@
+// Flags: --no-experimental-websocket
+'use strict';
+
+require('../common');
+const assert = require('assert');
+
+assert.strictEqual(typeof WebSocket, 'undefined');
diff --git a/test/parallel/test-websocket.js b/test/parallel/test-websocket.js
index 2a7069ccf3b739..c595ec12bfb66c 100644
--- a/test/parallel/test-websocket.js
+++ b/test/parallel/test-websocket.js
@@ -1,4 +1,3 @@
-// Flags: --experimental-websocket
 'use strict';
 
 require('../common');