diff --git a/src/app/pages/client/ClientNonUIFeatures.tsx b/src/app/pages/client/ClientNonUIFeatures.tsx
index cb5f906c5..7d3e64ca1 100644
--- a/src/app/pages/client/ClientNonUIFeatures.tsx
+++ b/src/app/pages/client/ClientNonUIFeatures.tsx
@@ -510,7 +510,19 @@ function MessageNotifications() {
           // For thread replies widen the tag to room:thread so each thread
           // coalesces independently instead of clobbering the room's bucket.
           tag: threadId ? `${roomId}:${threadId}` : roomId,
-          data: { path: roomPath },
+          // [Gitea #203] Inline reply from the notification (Chrome/Android
+          // text-input actions). The SW posts the reply itself — it holds the
+          // access token for authenticated media already — so this works with
+          // the tab in the background or closed. Not offered for encrypted
+          // rooms: the SW cannot encrypt.
+          ...(encrypted
+            ? {}
+            : {
+                // `actions` is SW-notification-only and not in lib.dom's
+                // NotificationOptions typing.
+                actions: [{ action: 'reply', title: 'Reply', type: 'text', placeholder: 'Reply…' }],
+              }),
+          data: { path: roomPath, roomId, threadId: threadId || undefined },
         },
         () => {
           window.focus();
diff --git a/src/app/utils/dom.ts b/src/app/utils/dom.ts
index 9c06b00e5..a2d46242c 100644
--- a/src/app/utils/dom.ts
+++ b/src/app/utils/dom.ts
@@ -278,7 +278,11 @@ const isDesktopApp = (): boolean =>
 
 export const showOsNotification = async (
   title: string,
-  options: NotificationOptions & { data?: { path?: string } },
+  options: NotificationOptions & {
+    data?: { path?: string; roomId?: string; threadId?: string };
+    /** Chrome/Android SW notifications: buttons, incl. text-input replies. */
+    actions?: { action: string; title: string; type?: 'button' | 'text'; placeholder?: string }[];
+  },
   onClick?: () => void,
 ): Promise<void> => {
   try {
diff --git a/src/sw.ts b/src/sw.ts
index 947d38613..b049c3680 100644
--- a/src/sw.ts
+++ b/src/sw.ts
@@ -1,6 +1,7 @@
 /// <reference lib="WebWorker" />
 
 import { precacheAndRoute, type PrecacheEntry } from 'workbox-precaching';
+import { sendNotificationReply } from './swReply';
 
 export type {};
 declare const self: ServiceWorkerGlobalScope & {
@@ -147,6 +148,32 @@ self.addEventListener('notificationclick', (event: NotificationEvent) => {
   const data = event.notification.data ?? {};
   const path = typeof data.path === 'string' ? data.path : undefined;
 
+  // [Gitea #203] Reply action: send it and stop — no need to raise the app.
+  if (event.action === 'reply' && typeof data.roomId === 'string') {
+    const text = (event as NotificationEvent & { reply?: string }).reply?.trim();
+    if (text) {
+      event.waitUntil(
+        sendNotificationReply(
+          Array.from(sessions.values()).pop(),
+          data.roomId,
+          data.threadId,
+          text,
+        ).then((ok) => {
+          if (!ok) {
+            // Let the user know it didn't go out, and keep their text reachable.
+            return self.registration.showNotification('Reply not sent', {
+              body: `Couldn't send "${text.slice(0, 60)}" — open the app to retry.`,
+              tag: `swreply-fail-${data.roomId}`,
+              data: { path },
+            });
+          }
+          return undefined;
+        }),
+      );
+      return;
+    }
+  }
+
   event.waitUntil(
     (async () => {
       const windowClients = (
diff --git a/src/swReply.test.ts b/src/swReply.test.ts
new file mode 100644
index 000000000..c7763f5a7
--- /dev/null
+++ b/src/swReply.test.ts
@@ -0,0 +1,58 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { buildReplyContent, replySendUrl, sendNotificationReply } from './swReply';
+
+test('thread replies carry the m.thread relation, room replies do not', () => {
+  assert.deepEqual(buildReplyContent('hi'), { msgtype: 'm.text', body: 'hi', 'm.mentions': {} });
+  assert.deepEqual(buildReplyContent('hi', '$root')['m.relates_to'], {
+    rel_type: 'm.thread',
+    event_id: '$root',
+    is_falling_back: true,
+    'm.in_reply_to': { event_id: '$root' },
+  });
+});
+
+test('send URL encodes the room id against the session base URL', () => {
+  assert.equal(
+    replySendUrl('https://matrix.example.org/', '!r:example.org', 'tx1'),
+    'https://matrix.example.org/_matrix/client/v3/rooms/!r%3Aexample.org/send/m.room.message/tx1',
+  );
+});
+
+test('sendNotificationReply PUTs with the bearer token and reports ok / failure', async () => {
+  const calls: { url: string; init: RequestInit }[] = [];
+  const fetchOk = (async (url: string, init: RequestInit) => {
+    calls.push({ url, init });
+    return { ok: true } as Response;
+  }) as unknown as typeof fetch;
+  assert.equal(
+    await sendNotificationReply(
+      { accessToken: 'tok', baseUrl: 'https://hs' },
+      '!r:hs',
+      '$t',
+      'yo',
+      fetchOk,
+    ),
+    true,
+  );
+  assert.equal(calls[0].init.method, 'PUT');
+  assert.equal((calls[0].init.headers as Record<string, string>).Authorization, 'Bearer tok');
+  assert.match(
+    calls[0].url,
+    /^https:\/\/hs\/_matrix\/client\/v3\/rooms\/!r%3Ahs\/send\/m\.room\.message\/swreply-/,
+  );
+  assert.equal(JSON.parse(calls[0].init.body as string)['m.relates_to'].event_id, '$t');
+
+  const fetchFail = (async () => ({ ok: false }) as Response) as unknown as typeof fetch;
+  assert.equal(
+    await sendNotificationReply(
+      { accessToken: 'tok', baseUrl: 'https://hs' },
+      '!r:hs',
+      undefined,
+      'yo',
+      fetchFail,
+    ),
+    false,
+  );
+  assert.equal(await sendNotificationReply(undefined, '!r:hs', undefined, 'yo', fetchOk), false);
+});
diff --git a/src/swReply.ts b/src/swReply.ts
new file mode 100644
index 000000000..968918567
--- /dev/null
+++ b/src/swReply.ts
@@ -0,0 +1,49 @@
+/**
+ * [Gitea #203] Build and send an inline reply typed into a notification's
+ * text action. Lives outside sw.ts so it can be unit-tested; the SW passes in
+ * its newest known session and the global fetch.
+ */
+export type SwReplySession = { accessToken: string; baseUrl: string };
+
+export const buildReplyContent = (text: string, threadId?: string): Record<string, unknown> => {
+  const content: Record<string, unknown> = { msgtype: 'm.text', body: text, 'm.mentions': {} };
+  if (threadId) {
+    content['m.relates_to'] = {
+      rel_type: 'm.thread',
+      event_id: threadId,
+      is_falling_back: true,
+      'm.in_reply_to': { event_id: threadId },
+    };
+  }
+  return content;
+};
+
+export const replySendUrl = (baseUrl: string, roomId: string, txnId: string): string =>
+  new URL(
+    `/_matrix/client/v3/rooms/${encodeURIComponent(roomId)}/send/m.room.message/${txnId}`,
+    baseUrl,
+  ).href;
+
+export async function sendNotificationReply(
+  session: SwReplySession | undefined,
+  roomId: string,
+  threadId: string | undefined,
+  text: string,
+  fetchFn: typeof fetch = fetch,
+): Promise<boolean> {
+  if (!session?.accessToken || !session.baseUrl) return false;
+  const txn = `swreply-${Date.now()}-${Math.random().toString(36).slice(2, 8)}`;
+  try {
+    const res = await fetchFn(replySendUrl(session.baseUrl, roomId, txn), {
+      method: 'PUT',
+      headers: {
+        Authorization: `Bearer ${session.accessToken}`,
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify(buildReplyContent(text, threadId)),
+    });
+    return res.ok;
+  } catch {
+    return false;
+  }
+}