diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3b12624c4..430c7febf 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -57,6 +57,7 @@
 
 ### Fixes
 - Messages: make `/stop` clear queued followups and pending session lane work for a hard abort.
+- Messages: make `/stop` abort active sub-agent runs spawned from the requester session and report how many were stopped.
 - WhatsApp: default response prefix only for self-chat, using identity name when set.
 - Signal/iMessage: bound transport readiness waits to 30s with periodic logging. (#1014) — thanks @Szpadel.
 - Auth: merge main auth profiles into per-agent stores for sub-agents and document inheritance. (#1013) — thanks @marcmarg.
diff --git a/docs/concepts/session.md b/docs/concepts/session.md
index b90493267..0fe0b2414 100644
--- a/docs/concepts/session.md
+++ b/docs/concepts/session.md
@@ -106,7 +106,7 @@ Send these as standalone messages so they register.
 - `clawdbot gateway call sessions.list --params '{}'` — fetch sessions from the running gateway (use `--url`/`--token` for remote gateway access).
 - Send `/status` as a standalone message in chat to see whether the agent is reachable, how much of the session context is used, current thinking/verbose toggles, and when your WhatsApp web creds were last refreshed (helps spot relink needs).
 - Send `/context list` or `/context detail` to see what’s in the system prompt and injected workspace files (and the biggest context contributors).
-- Send `/stop` as a standalone message to abort the current run and clear queued followups for that session.
+- Send `/stop` as a standalone message to abort the current run, clear queued followups for that session, and stop any sub-agent runs spawned from it (the reply includes the stopped count).
 - Send `/compact` (optional instructions) as a standalone message to summarize older context and free up window space. See [/concepts/compaction](/concepts/compaction).
 - JSONL transcripts can be opened directly to review full turns.
 
diff --git a/docs/tools/subagents.md b/docs/tools/subagents.md
index 2ac3b57d4..07c33cb44 100644
--- a/docs/tools/subagents.md
+++ b/docs/tools/subagents.md
@@ -108,6 +108,11 @@ Sub-agents use a dedicated in-process queue lane:
 - Lane name: `subagent`
 - Concurrency: `agents.defaults.subagents.maxConcurrent` (default `1`)
 
+## Stopping
+
+- Sending `/stop` in the requester chat aborts the requester session and stops any active sub-agent runs spawned from it.
+- The `/stop` reply includes how many sub-agent runs were stopped.
+
 ## Limitations
 
 - Sub-agent announce is **best-effort**. If the gateway restarts, pending “announce back” work is lost.
diff --git a/src/agents/subagent-registry.ts b/src/agents/subagent-registry.ts
index 73c4417d5..3dd821bef 100644
--- a/src/agents/subagent-registry.ts
+++ b/src/agents/subagent-registry.ts
@@ -354,6 +354,12 @@ export function releaseSubagentRun(runId: string) {
   if (subagentRuns.size === 0) stopSweeper();
 }
 
+export function listSubagentRunsForRequester(requesterSessionKey: string): SubagentRunRecord[] {
+  const key = requesterSessionKey.trim();
+  if (!key) return [];
+  return [...subagentRuns.values()].filter((entry) => entry.requesterSessionKey === key);
+}
+
 export function initSubagentRegistry() {
   restoreSubagentRunsOnce();
 }
diff --git a/src/auto-reply/reply.triggers.trigger-handling.filters-usage-summary-current-model-provider.test.ts b/src/auto-reply/reply.triggers.trigger-handling.filters-usage-summary-current-model-provider.test.ts
index fd43f3a0c..6403627d5 100644
--- a/src/auto-reply/reply.triggers.trigger-handling.filters-usage-summary-current-model-provider.test.ts
+++ b/src/auto-reply/reply.triggers.trigger-handling.filters-usage-summary-current-model-provider.test.ts
@@ -222,7 +222,7 @@ describe("trigger handling", () => {
         makeCfg(home),
       );
       const text = Array.isArray(res) ? res[0]?.text : res?.text;
-      expect(text).toBe("⚙️ Agent was aborted.");
+      expect(text).toBe("⚙️ Agent was aborted. Stopped 0 sub-agents.");
       expect(runEmbeddedPiAgent).not.toHaveBeenCalled();
     });
   });
@@ -238,7 +238,7 @@ describe("trigger handling", () => {
         makeCfg(home),
       );
       const text = Array.isArray(res) ? res[0]?.text : res?.text;
-      expect(text).toBe("⚙️ Agent was aborted.");
+      expect(text).toBe("⚙️ Agent was aborted. Stopped 0 sub-agents.");
       expect(runEmbeddedPiAgent).not.toHaveBeenCalled();
     });
   });
diff --git a/src/auto-reply/reply.triggers.trigger-handling.targets-active-session-native-stop.test.ts b/src/auto-reply/reply.triggers.trigger-handling.targets-active-session-native-stop.test.ts
index be6393c25..5768fad42 100644
--- a/src/auto-reply/reply.triggers.trigger-handling.targets-active-session-native-stop.test.ts
+++ b/src/auto-reply/reply.triggers.trigger-handling.targets-active-session-native-stop.test.ts
@@ -159,7 +159,7 @@ describe("trigger handling", () => {
       );
 
       const text = Array.isArray(res) ? res[0]?.text : res?.text;
-      expect(text).toBe("⚙️ Agent was aborted.");
+      expect(text).toBe("⚙️ Agent was aborted. Stopped 0 sub-agents.");
       expect(vi.mocked(abortEmbeddedPiRun)).toHaveBeenCalledWith(targetSessionId);
       const store = loadSessionStore(cfg.session.store);
       expect(store[targetSessionKey]?.abortedLastRun).toBe(true);
diff --git a/src/auto-reply/reply/abort.test.ts b/src/auto-reply/reply/abort.test.ts
index 3bd21633b..31d8efae5 100644
--- a/src/auto-reply/reply/abort.test.ts
+++ b/src/auto-reply/reply/abort.test.ts
@@ -18,6 +18,14 @@ const commandQueueMocks = vi.hoisted(() => ({
 
 vi.mock("../../process/command-queue.js", () => commandQueueMocks);
 
+const subagentRegistryMocks = vi.hoisted(() => ({
+  listSubagentRunsForRequester: vi.fn(() => []),
+}));
+
+vi.mock("../../agents/subagent-registry.js", () => ({
+  listSubagentRunsForRequester: subagentRegistryMocks.listSubagentRunsForRequester,
+}));
+
 describe("abort detection", () => {
   it("triggerBodyNormalized extracts /stop from RawBody for abort detection", async () => {
     const root = await fs.mkdtemp(path.join(os.tmpdir(), "clawdbot-abort-"));
@@ -137,4 +145,59 @@ describe("abort detection", () => {
     expect(getFollowupQueueDepth(sessionKey)).toBe(0);
     expect(commandQueueMocks.clearCommandLane).toHaveBeenCalledWith(`session:${sessionKey}`);
   });
+
+  it("fast-abort stops active subagent runs for requester session", async () => {
+    const root = await fs.mkdtemp(path.join(os.tmpdir(), "clawdbot-abort-"));
+    const storePath = path.join(root, "sessions.json");
+    const cfg = { session: { store: storePath } } as ClawdbotConfig;
+    const sessionKey = "telegram:parent";
+    const childKey = "agent:main:subagent:child-1";
+    const sessionId = "session-parent";
+    const childSessionId = "session-child";
+    await fs.writeFile(
+      storePath,
+      JSON.stringify(
+        {
+          [sessionKey]: {
+            sessionId,
+            updatedAt: Date.now(),
+          },
+          [childKey]: {
+            sessionId: childSessionId,
+            updatedAt: Date.now(),
+          },
+        },
+        null,
+        2,
+      ),
+    );
+
+    subagentRegistryMocks.listSubagentRunsForRequester.mockReturnValueOnce([
+      {
+        runId: "run-1",
+        childSessionKey: childKey,
+        requesterSessionKey: sessionKey,
+        requesterDisplayKey: "telegram:parent",
+        task: "do work",
+        cleanup: "keep",
+        createdAt: Date.now(),
+      },
+    ]);
+
+    const result = await tryFastAbortFromMessage({
+      ctx: {
+        CommandBody: "/stop",
+        RawBody: "/stop",
+        SessionKey: sessionKey,
+        Provider: "telegram",
+        Surface: "telegram",
+        From: "telegram:parent",
+        To: "telegram:parent",
+      },
+      cfg,
+    });
+
+    expect(result.stoppedSubagents).toBe(1);
+    expect(commandQueueMocks.clearCommandLane).toHaveBeenCalledWith(`session:${childKey}`);
+  });
 });
diff --git a/src/auto-reply/reply/abort.ts b/src/auto-reply/reply/abort.ts
index da60cdc9f..65f221ba9 100644
--- a/src/auto-reply/reply/abort.ts
+++ b/src/auto-reply/reply/abort.ts
@@ -1,5 +1,6 @@
 import { resolveSessionAgentId } from "../../agents/agent-scope.js";
 import { abortEmbeddedPiRun } from "../../agents/pi-embedded.js";
+import { listSubagentRunsForRequester } from "../../agents/subagent-registry.js";
 import type { ClawdbotConfig } from "../../config/config.js";
 import {
   loadSessionStore,
@@ -14,6 +15,7 @@ import type { MsgContext } from "../templating.js";
 import { logVerbose } from "../../globals.js";
 import { stripMentions, stripStructuralPrefixes } from "./mentions.js";
 import { clearSessionQueues } from "./queue.js";
+import { resolveInternalSessionKey, resolveMainSessionAlias } from "../../agents/tools/sessions-helpers.js";
 
 const ABORT_TRIGGERS = new Set(["stop", "esc", "abort", "wait", "exit", "interrupt"]);
 const ABORT_MEMORY = new Map<string, boolean>();
@@ -32,6 +34,14 @@ export function setAbortMemory(key: string, value: boolean): void {
   ABORT_MEMORY.set(key, value);
 }
 
+export function formatAbortReplyText(stoppedSubagents?: number): string {
+  if (typeof stoppedSubagents !== "number") {
+    return "⚙️ Agent was aborted.";
+  }
+  const label = stoppedSubagents === 1 ? "sub-agent" : "sub-agents";
+  return `⚙️ Agent was aborted. Stopped ${stoppedSubagents} ${label}.`;
+}
+
 function resolveSessionEntryForKey(
   store: Record<string, SessionEntry> | undefined,
   sessionKey: string | undefined,
@@ -54,10 +64,62 @@ function resolveAbortTargetKey(ctx: MsgContext): string | undefined {
   return sessionKey || undefined;
 }
 
+function normalizeRequesterSessionKey(
+  cfg: ClawdbotConfig,
+  key: string | undefined,
+): string | undefined {
+  const cleaned = key?.trim();
+  if (!cleaned) return undefined;
+  const { mainKey, alias } = resolveMainSessionAlias(cfg);
+  return resolveInternalSessionKey({ key: cleaned, alias, mainKey });
+}
+
+export function stopSubagentsForRequester(params: {
+  cfg: ClawdbotConfig;
+  requesterSessionKey?: string;
+}): { stopped: number } {
+  const requesterKey = normalizeRequesterSessionKey(params.cfg, params.requesterSessionKey);
+  if (!requesterKey) return { stopped: 0 };
+  const runs = listSubagentRunsForRequester(requesterKey);
+  if (runs.length === 0) return { stopped: 0 };
+
+  const storeCache = new Map<string, Record<string, SessionEntry>>();
+  const seenChildKeys = new Set<string>();
+  let stopped = 0;
+
+  for (const run of runs) {
+    if (run.endedAt) continue;
+    const childKey = run.childSessionKey?.trim();
+    if (!childKey || seenChildKeys.has(childKey)) continue;
+    seenChildKeys.add(childKey);
+
+    const cleared = clearSessionQueues([childKey]);
+    const parsed = parseAgentSessionKey(childKey);
+    const storePath = resolveStorePath(params.cfg.session?.store, { agentId: parsed?.agentId });
+    let store = storeCache.get(storePath);
+    if (!store) {
+      store = loadSessionStore(storePath);
+      storeCache.set(storePath, store);
+    }
+    const entry = store[childKey];
+    const sessionId = entry?.sessionId;
+    const aborted = sessionId ? abortEmbeddedPiRun(sessionId) : false;
+
+    if (aborted || cleared.followupCleared > 0 || cleared.laneCleared > 0) {
+      stopped += 1;
+    }
+  }
+
+  if (stopped > 0) {
+    logVerbose(`abort: stopped ${stopped} subagent run(s) for ${requesterKey}`);
+  }
+  return { stopped };
+}
+
 export async function tryFastAbortFromMessage(params: {
   ctx: MsgContext;
   cfg: ClawdbotConfig;
-}): Promise<{ handled: boolean; aborted: boolean }> {
+}): Promise<{ handled: boolean; aborted: boolean; stoppedSubagents?: number }> {
   const { ctx, cfg } = params;
   const commandAuthorized = ctx.CommandAuthorized ?? true;
   const auth = resolveCommandAuthorization({
@@ -81,6 +143,7 @@ export async function tryFastAbortFromMessage(params: {
   if (!abortRequested) return { handled: false, aborted: false };
 
   const abortKey = targetKey ?? auth.from ?? auth.to;
+  const requesterSessionKey = targetKey ?? ctx.SessionKey ?? abortKey;
 
   if (targetKey) {
     const storePath = resolveStorePath(cfg.session?.store, { agentId });
@@ -108,11 +171,13 @@ export async function tryFastAbortFromMessage(params: {
     } else if (abortKey) {
       setAbortMemory(abortKey, true);
     }
-    return { handled: true, aborted };
+    const { stopped } = stopSubagentsForRequester({ cfg, requesterSessionKey });
+    return { handled: true, aborted, stoppedSubagents: stopped };
   }
 
   if (abortKey) {
     setAbortMemory(abortKey, true);
   }
-  return { handled: true, aborted: false };
+  const { stopped } = stopSubagentsForRequester({ cfg, requesterSessionKey });
+  return { handled: true, aborted: false, stoppedSubagents: stopped };
 }
diff --git a/src/auto-reply/reply/commands-session.ts b/src/auto-reply/reply/commands-session.ts
index 2391e512d..60b201214 100644
--- a/src/auto-reply/reply/commands-session.ts
+++ b/src/auto-reply/reply/commands-session.ts
@@ -6,7 +6,7 @@ import { scheduleGatewaySigusr1Restart, triggerClawdbotRestart } from "../../inf
 import { parseAgentSessionKey } from "../../routing/session-key.js";
 import { parseActivationCommand } from "../group-activation.js";
 import { parseSendPolicyCommand } from "../send-policy.js";
-import { isAbortTrigger, setAbortMemory } from "./abort.js";
+import { formatAbortReplyText, isAbortTrigger, setAbortMemory, stopSubagentsForRequester } from "./abort.js";
 import { clearSessionQueues } from "./queue.js";
 import type { CommandHandler } from "./commands-types.js";
 
@@ -208,7 +208,14 @@ export const handleStopCommand: CommandHandler = async (params, allowTextCommand
   } else if (params.command.abortKey) {
     setAbortMemory(params.command.abortKey, true);
   }
-  return { shouldContinue: false, reply: { text: "⚙️ Agent was aborted." } };
+  const { stopped } = stopSubagentsForRequester({
+    cfg: params.cfg,
+    requesterSessionKey: abortTarget.key ?? params.sessionKey,
+  });
+  return {
+    shouldContinue: false,
+    reply: { text: formatAbortReplyText(stopped) },
+  };
 };
 
 export const handleAbortTrigger: CommandHandler = async (params, allowTextCommands) => {
@@ -241,5 +248,12 @@ export const handleAbortTrigger: CommandHandler = async (params, allowTextComman
   } else if (params.command.abortKey) {
     setAbortMemory(params.command.abortKey, true);
   }
-  return { shouldContinue: false, reply: { text: "⚙️ Agent was aborted." } };
+  const { stopped } = stopSubagentsForRequester({
+    cfg: params.cfg,
+    requesterSessionKey: abortTarget.key ?? params.sessionKey,
+  });
+  return {
+    shouldContinue: false,
+    reply: { text: formatAbortReplyText(stopped) },
+  };
 };
diff --git a/src/auto-reply/reply/dispatch-from-config.test.ts b/src/auto-reply/reply/dispatch-from-config.test.ts
index 96cd2942d..bc8d048e5 100644
--- a/src/auto-reply/reply/dispatch-from-config.test.ts
+++ b/src/auto-reply/reply/dispatch-from-config.test.ts
@@ -24,6 +24,11 @@ vi.mock("./route-reply.js", () => ({
 
 vi.mock("./abort.js", () => ({
   tryFastAbortFromMessage: mocks.tryFastAbortFromMessage,
+  formatAbortReplyText: (stoppedSubagents?: number) => {
+    if (typeof stoppedSubagents !== "number") return "⚙️ Agent was aborted.";
+    const label = stoppedSubagents === 1 ? "sub-agent" : "sub-agents";
+    return `⚙️ Agent was aborted. Stopped ${stoppedSubagents} ${label}.`;
+  },
 }));
 
 const { dispatchReplyFromConfig } = await import("./dispatch-from-config.js");
@@ -123,6 +128,31 @@ describe("dispatchReplyFromConfig", () => {
     });
   });
 
+  it("fast-abort reply includes stopped subagent count when provided", async () => {
+    mocks.tryFastAbortFromMessage.mockResolvedValue({
+      handled: true,
+      aborted: true,
+      stoppedSubagents: 2,
+    });
+    const cfg = {} as ClawdbotConfig;
+    const dispatcher = createDispatcher();
+    const ctx: MsgContext = {
+      Provider: "telegram",
+      Body: "/stop",
+    };
+
+    await dispatchReplyFromConfig({
+      ctx,
+      cfg,
+      dispatcher,
+      replyResolver: vi.fn(async () => ({ text: "hi" }) as ReplyPayload),
+    });
+
+    expect(dispatcher.sendFinalReply).toHaveBeenCalledWith({
+      text: "⚙️ Agent was aborted. Stopped 2 sub-agents.",
+    });
+  });
+
   it("deduplicates inbound messages by MessageSid and origin", async () => {
     mocks.tryFastAbortFromMessage.mockResolvedValue({
       handled: false,
diff --git a/src/auto-reply/reply/dispatch-from-config.ts b/src/auto-reply/reply/dispatch-from-config.ts
index 7b81d9c94..c7a766fed 100644
--- a/src/auto-reply/reply/dispatch-from-config.ts
+++ b/src/auto-reply/reply/dispatch-from-config.ts
@@ -3,7 +3,7 @@ import { logVerbose } from "../../globals.js";
 import { getReplyFromConfig } from "../reply.js";
 import type { MsgContext } from "../templating.js";
 import type { GetReplyOptions, ReplyPayload } from "../types.js";
-import { tryFastAbortFromMessage } from "./abort.js";
+import { formatAbortReplyText, tryFastAbortFromMessage } from "./abort.js";
 import { shouldSkipDuplicateInbound } from "./inbound-dedupe.js";
 import type { ReplyDispatcher, ReplyDispatchKind } from "./reply-dispatcher.js";
 import { isRoutableChannel, routeReply } from "./route-reply.js";
@@ -70,7 +70,9 @@ export async function dispatchReplyFromConfig(params: {
 
   const fastAbort = await tryFastAbortFromMessage({ ctx, cfg });
   if (fastAbort.handled) {
-    const payload = { text: "⚙️ Agent was aborted." } satisfies ReplyPayload;
+    const payload = {
+      text: formatAbortReplyText(fastAbort.stoppedSubagents),
+    } satisfies ReplyPayload;
     let queuedFinal = false;
     let routedFinalCount = 0;
     if (shouldRouteToOriginating && originatingChannel && originatingTo) {