diff --git a/src/content/changelog/durable-objects/2026-02-24-deleteall-deletes-alarms.mdx b/src/content/changelog/durable-objects/2026-02-24-deleteall-deletes-alarms.mdx
new file mode 100644
index 00000000000..3e807c65636
--- /dev/null
+++ b/src/content/changelog/durable-objects/2026-02-24-deleteall-deletes-alarms.mdx
@@ -0,0 +1,23 @@
+---
+title: deleteAll() now deletes Durable Object alarm
+description: Clean up a Durable Object's storage with a single API call.
+products:
+  - durable-objects
+  - workers
+date: 2026-02-24
+---
+
+`deleteAll()` now deletes a Durable Object alarm in addition to stored data for Workers with a compatibility date of `2026-02-24` or later. This change simplifies clearing a Durable Object's storage with a single API call.
+
+Previously, `deleteAll()` only deleted user-stored data for an object. Alarm usage stores metadata in an object's storage, which required a separate `deleteAlarm()` call to fully clean up all storage for an object. The `deleteAll()` change applies to both KV-backed and SQLite-backed Durable Objects.
+
+```js
+// Before: two API calls required to clear all storage
+await this.ctx.storage.deleteAlarm();
+await this.ctx.storage.deleteAll();
+
+// Now: a single call clears both data and the alarm
+await this.ctx.storage.deleteAll();
+```
+
+For more information, refer to the [Storage API documentation](/durable-objects/api/sqlite-storage-api/#deleteall).
diff --git a/src/content/compatibility-flags/delete-all-deletes-alarm.md b/src/content/compatibility-flags/delete-all-deletes-alarm.md
new file mode 100644
index 00000000000..ba7c94d50de
--- /dev/null
+++ b/src/content/compatibility-flags/delete-all-deletes-alarm.md
@@ -0,0 +1,14 @@
+---
+_build:
+  publishResources: false
+  render: never
+  list: never
+
+name: "Durable Object `deleteAll()` deletes alarms"
+sort_date: "2026-02-24"
+enable_date: "2026-02-24"
+enable_flag: "delete_all_deletes_alarm"
+disable_flag: "delete_all_preserves_alarm"
+---
+
+With the `delete_all_deletes_alarm` flag set, calling `deleteAll()` on a Durable Object's storage will delete any active alarm in addition to all stored data. Previously, `deleteAll()` only deleted user-stored data, and alarms required a separate `deleteAlarm()` call to remove. This change applies to both KV-backed and SQLite-backed Durable Objects.
diff --git a/src/content/docs/durable-objects/best-practices/rules-of-durable-objects.mdx b/src/content/docs/durable-objects/best-practices/rules-of-durable-objects.mdx
index d4e3a77575c..50430798145 100644
--- a/src/content/docs/durable-objects/best-practices/rules-of-durable-objects.mdx
+++ b/src/content/docs/durable-objects/best-practices/rules-of-durable-objects.mdx
@@ -1410,7 +1410,7 @@ export class Subscription extends DurableObject<Env> {
 
 ### Clean up storage with `deleteAll()`
 
-To fully clear a Durable Object's storage, call `deleteAll()`. Simply deleting individual keys or dropping tables is not sufficient, as some internal metadata may remain. If you have alarms set, delete those first.
+To fully clear a Durable Object's storage, call `deleteAll()`. Simply deleting individual keys or dropping tables is not sufficient, as some internal metadata may remain. Workers with a compatibility date before [2026-02-24](/workers/configuration/compatibility-flags/#delete-all-deletes-alarms) and an alarm set should delete the alarm first with `deleteAlarm()`.
 
 <TypeScriptExample filename="index.ts">
 ```ts
@@ -1422,10 +1422,8 @@ export interface Env {
 
 export class ChatRoom extends DurableObject<Env> {
 	async clearStorage() {
-		// If you have an alarm set, delete it first
-		await this.ctx.storage.deleteAlarm();
 
-		// Delete all storage
+		// Delete all storage, including any set alarm
 		await this.ctx.storage.deleteAll();
 
 		// The Durable Object instance still exists, but with empty storage
diff --git a/src/content/partials/durable-objects/api-storage-other-methods.mdx b/src/content/partials/durable-objects/api-storage-other-methods.mdx
index 035241a0c60..44553d94354 100644
--- a/src/content/partials/durable-objects/api-storage-other-methods.mdx
+++ b/src/content/partials/durable-objects/api-storage-other-methods.mdx
@@ -9,7 +9,7 @@ import { Type, MetaInfo } from "~/components";
 - <code>deleteAll(options <Type text="Object" /> <MetaInfo text="optional" />)</code>: <Type text="Promise" />
   - Deletes all stored data, effectively deallocating all storage used by the Durable Object. For Durable Objects with a key-value storage backend, `deleteAll()` removes all keys and associated values for an individual Durable Object. For Durable Objects with a [SQLite storage backend](/durable-objects/best-practices/access-durable-objects-storage/#create-sqlite-backed-durable-object-class), `deleteAll()` removes the entire contents of a Durable Object's private SQLite database, including both SQL data and key-value data.
   - For Durable Objects with a key-value storage backend, an in-progress `deleteAll()` operation can fail, which may leave a subset of data undeleted. Durable Objects with a SQLite storage backend do not have a partial `deleteAll()` issue because `deleteAll()` operations are atomic (all or nothing).
-  - `deleteAll()` does not proactively delete [alarms](/durable-objects/api/alarms/). Use [`deleteAlarm()`](/durable-objects/api/alarms/#deletealarm) to delete an alarm.
+  - For Workers with a compatibility date of `2026-02-24` or later, `deleteAll()` also deletes any active [alarm](/durable-objects/api/alarms/). For earlier compatibility dates, `deleteAll()` does not delete alarms. Use [`deleteAlarm()`](/durable-objects/api/alarms/#deletealarm) separately, or enable the `delete_all_deletes_alarm` [compatibility flag](/workers/configuration/compatibility-flags/).
 
 ### `transactionSync`