diff --git a/baselines/dom.generated.d.ts b/baselines/dom.generated.d.ts
index 6d4e376b8..10a3151aa 100644
--- a/baselines/dom.generated.d.ts
+++ b/baselines/dom.generated.d.ts
@@ -18827,6 +18827,7 @@ declare var Worklet: {
 interface WritableStream<W = any> {
     readonly locked: boolean;
     abort(reason?: any): Promise<void>;
+    close(): Promise<void>;
     getWriter(): WritableStreamDefaultWriter<W>;
 }
 
diff --git a/baselines/webworker.generated.d.ts b/baselines/webworker.generated.d.ts
index 8f1f9071a..fe0c57abd 100644
--- a/baselines/webworker.generated.d.ts
+++ b/baselines/webworker.generated.d.ts
@@ -5469,6 +5469,7 @@ interface WorkerUtils extends WindowBase64 {
 interface WritableStream<W = any> {
     readonly locked: boolean;
     abort(reason?: any): Promise<void>;
+    close(): Promise<void>;
     getWriter(): WritableStreamDefaultWriter<W>;
 }
 
diff --git a/inputfiles/idl/Streams.widl b/inputfiles/idl/Streams.widl
index 2fd1f3890..147e17097 100644
--- a/inputfiles/idl/Streams.widl
+++ b/inputfiles/idl/Streams.widl
@@ -114,6 +114,7 @@ interface ReadableStreamBYOBRequest {
 interface WritableStream {
     readonly attribute boolean locked;
     Promise<void> abort(optional any reason);
+    Promise<void> close();
     WritableStreamDefaultWriter getWriter();
 };