diff --git a/README.md b/README.md
index 2f54faa..1d57e22 100644
--- a/README.md
+++ b/README.md
@@ -22,6 +22,7 @@ kill-the-news keeps the same workflow while avoiding shared domains and shared d
 - Cloudflare Email Workers ingestion (no third-party service)
 - ForwardEmail webhook ingestion with source-IP verification (optional alternative)
 - Optional per-feed sender allowlist (`email@domain.com` or `domain.com`)
+- Optional per-feed "sender in title" toggle — renders each entry as `[Sender] Subject` for at-a-glance scanning in your reader
 - RSS generation on demand (`/rss/:feedId`)
 - Atom feed at `/atom/:feedId`
 - JSON Feed at `/json/:feedId` (natively consumed by NetNewsWire, Reeder, NewsBlur, Feedly)
diff --git a/TODO.md b/TODO.md
index 5d85d5e..64b829e 100644
--- a/TODO.md
+++ b/TODO.md
@@ -62,7 +62,7 @@ Gaps found by reading every open/closed issue + PR on [kill-the-newsletter](http
 
 - [ ] `P2·S` **Strip-styles / plaintext rendering option** ([#74](https://github.com/leafac/kill-the-newsletter/issues/74), [#119](https://github.com/leafac/kill-the-newsletter/issues/119)). Some readers render newsletter HTML/CSS poorly. Offer an opt-in to strip `<style>` + inline styles (keeping links), or to prefer the `text/plain` part. Per-feed setting + `src/infrastructure/html-processor.ts`.
 
-- [ ] `P2·S` **Optional sender in entry title** ([#123 — open PR upstream](https://github.com/leafac/kill-the-newsletter/pull/123), [#124](https://github.com/leafac/kill-the-newsletter/issues/124)). We already emit `<author>`, but some users want `[Sender] Subject` as the entry title for at-a-glance scanning in the reader. Per-feed toggle + `src/infrastructure/feed-generator.ts`.
+- [x] `P2·S` **Optional sender in entry title** ([#123 — open PR upstream](https://github.com/leafac/kill-the-newsletter/pull/123), [#124](https://github.com/leafac/kill-the-newsletter/issues/124)). We already emit `<author>`, but some users want `[Sender] Subject` as the entry title for at-a-glance scanning in the reader. Per-feed toggle + `src/infrastructure/feed-generator.ts`. — **Shipped:** per-feed `senderInTitle` flag (domain `FeedState.senderInTitle` ↔ `FeedConfig.sender_in_title`); when set, `buildFeed` prefixes each entry title with `[Sender]` (display name, falling back to the email address). Toggle exposed as an admin edit-form checkbox and on the REST API (`FeedCreate`/`FeedUpdate`/`Feed` schemas).
 
 - [ ] `P2·S` **Detect a newsletter's native Atom/RSS feed** — _top item on upstream's own [TODO](https://github.com/leafac/kill-the-newsletter/blob/main/TODO.md), not yet built there_. When an incoming email's HTML contains `<link rel="alternate" type="application/atom+xml">` (or `application/rss+xml`), surface it: "this newsletter already publishes a feed — subscribe to it directly instead." We already parse HTML with linkedom in `src/infrastructure/html-processor.ts`, so detection is cheap; store the discovered URL on the feed and show it in the admin UI / a feed entry. A genuine differentiator — we'd ship it before upstream.
 
diff --git a/src/domain/feed-state.ts b/src/domain/feed-state.ts
index d249f78..59a778a 100644
--- a/src/domain/feed-state.ts
+++ b/src/domain/feed-state.ts
@@ -15,6 +15,8 @@ export interface FeedState {
    * is `mailboxId@domain`. Decoupled from the feed's `FeedId` (the read id). */
   mailboxId: string;
   author?: string;
+  /** When true, entry titles in the feed output are rendered as `[Sender] Subject`. */
+  senderInTitle?: boolean;
   allowedSenders: string[];
   blockedSenders: string[];
   createdAt: number;
diff --git a/src/domain/feed.aggregate.ts b/src/domain/feed.aggregate.ts
index 6779e97..88b4035 100644
--- a/src/domain/feed.aggregate.ts
+++ b/src/domain/feed.aggregate.ts
@@ -13,6 +13,8 @@ export interface CreateFeedInput {
   language: string;
   allowedSenders: string[];
   blockedSenders: string[];
+  /** When true, render entry titles as `[Sender] Subject` in the feed output. */
+  senderInTitle?: boolean;
   /** Raw client-requested lifetime; the application resolves it into a `Lifetime`. */
   lifetimeHours?: number;
 }
@@ -23,6 +25,7 @@ export interface UpdateFeedInput {
   language?: string;
   allowedSenders?: string[];
   blockedSenders?: string[];
+  senderInTitle?: boolean;
   lifetimeHours?: number;
 }
 
@@ -95,6 +98,7 @@ export class Feed {
       description: input.description,
       language: input.language,
       mailboxId: deps.mailboxId.value,
+      senderInTitle: input.senderInTitle,
       allowedSenders: input.allowedSenders,
       blockedSenders: input.blockedSenders,
       createdAt: now,
@@ -134,6 +138,11 @@ export class Feed {
     return this._state.language;
   }
 
+  /** Whether entry titles render as `[Sender] Subject` in the feed output. */
+  get senderInTitle(): boolean {
+    return this._state.senderInTitle ?? false;
+  }
+
   /** The inbound mailbox (`noun.noun.NN`) — the feed's email address is `mailboxId@domain`. */
   get mailboxId(): MailboxId {
     return MailboxId.unchecked(this._state.mailboxId);
@@ -341,6 +350,9 @@ export class Feed {
       this._state.description = patch.description;
     }
     if (patch.language !== undefined) this._state.language = patch.language;
+    if (patch.senderInTitle !== undefined) {
+      this._state.senderInTitle = patch.senderInTitle;
+    }
     if (patch.allowedSenders !== undefined) {
       this._state.allowedSenders = patch.allowedSenders;
     }
diff --git a/src/infrastructure/feed-generator.test.ts b/src/infrastructure/feed-generator.test.ts
index d0f0537..db887ca 100644
--- a/src/infrastructure/feed-generator.test.ts
+++ b/src/infrastructure/feed-generator.test.ts
@@ -147,6 +147,37 @@ describe("generateRssFeed", () => {
     expect(result).not.toContain("<item>");
   });
 
+  it("leaves the item title unprefixed by default", () => {
+    const result = generateRssFeed(
+      mockFeedConfig,
+      mockEmails,
+      BASE_URL,
+      FEED_ID,
+    );
+    expect(result).toContain("Hello World");
+    expect(result).not.toContain("[Alice]");
+  });
+
+  it("prefixes the item title with the sender when sender_in_title is set", () => {
+    const result = generateRssFeed(
+      { ...mockFeedConfig, sender_in_title: true },
+      mockEmails,
+      BASE_URL,
+      FEED_ID,
+    );
+    expect(result).toContain("[Alice] Hello World");
+  });
+
+  it("falls back to the email address when the sender has no display name", () => {
+    const result = generateRssFeed(
+      { ...mockFeedConfig, sender_in_title: true },
+      [{ ...mockEmails[0], from: "bob@example.com" }],
+      BASE_URL,
+      FEED_ID,
+    );
+    expect(result).toContain("[bob@example.com] Hello World");
+  });
+
   it("feed link points to the public read URL, never an admin path", () => {
     const result = generateRssFeed(
       mockFeedConfig,
diff --git a/src/infrastructure/feed-generator.ts b/src/infrastructure/feed-generator.ts
index fad14f7..169862a 100644
--- a/src/infrastructure/feed-generator.ts
+++ b/src/infrastructure/feed-generator.ts
@@ -74,8 +74,12 @@ function buildFeed(
       baseUrl,
       EmailAddress.parse(email.from)?.siteBaseUrl() ?? "",
     );
+    const subject = htmlToText(email.subject);
+    const title = feedConfig.sender_in_title
+      ? `[${parseFromAddress(email.from).name ?? email.from}] ${subject}`
+      : subject;
     feed.addItem({
-      title: htmlToText(email.subject),
+      title,
       id: entryUrl,
       link: entryUrl,
       description: bodyContent,
diff --git a/src/infrastructure/feed-mapper.ts b/src/infrastructure/feed-mapper.ts
index 1a74f17..69dd1d7 100644
--- a/src/infrastructure/feed-mapper.ts
+++ b/src/infrastructure/feed-mapper.ts
@@ -18,6 +18,7 @@ export function fromConfigDTO(dto: FeedConfig): FeedState {
     language: dto.language,
     mailboxId: dto.mailbox_id,
     author: dto.author,
+    senderInTitle: dto.sender_in_title,
     allowedSenders: dto.allowed_senders ?? [],
     blockedSenders: dto.blocked_senders ?? [],
     createdAt: dto.created_at,
@@ -34,6 +35,7 @@ export function toConfigDTO(state: FeedState): FeedConfig {
     language: state.language,
     mailbox_id: state.mailboxId,
     author: state.author,
+    sender_in_title: state.senderInTitle,
     allowed_senders: state.allowedSenders,
     blocked_senders: state.blockedSenders,
     created_at: state.createdAt,
diff --git a/src/routes/admin.test.ts b/src/routes/admin.test.ts
index a765934..122b05b 100644
--- a/src/routes/admin.test.ts
+++ b/src/routes/admin.test.ts
@@ -1472,4 +1472,104 @@ describe("Admin Routes", () => {
       expect(body).not.toContain("validator.w3.org/feed/images");
     });
   });
+
+  describe("Sender-in-title toggle", () => {
+    it("edit form renders the checkbox, unchecked by default", async () => {
+      const authCookie = await loginAndGetCookie();
+      const repo = FeedRepository.from(mockEnv as unknown as Env);
+      const feedId = FeedId.generate();
+      const feed = Feed.create(
+        feedId,
+        {
+          title: "Title Toggle Feed",
+          language: "en",
+          allowedSenders: [],
+          blockedSenders: [],
+        },
+        { mailboxId: MailboxId.unchecked("title.toggle.01") },
+      );
+      await repo.save(feed);
+
+      const res = await request(`/admin/feeds/${feedId.value}/edit`, {
+        headers: { Cookie: authCookie },
+      });
+      expect(res.status).toBe(200);
+      const body = await res.text();
+      expect(body).toContain('name="sender_in_title"');
+      expect(body).toContain("Show sender in entry titles");
+      expect(body).not.toContain("checked");
+    });
+
+    it("persists the toggle through edit and reflects it back as checked", async () => {
+      const authCookie = await loginAndGetCookie();
+      const repo = FeedRepository.from(mockEnv as unknown as Env);
+      const feedId = FeedId.generate();
+      const feed = Feed.create(
+        feedId,
+        {
+          title: "Title Toggle Feed",
+          language: "en",
+          allowedSenders: [],
+          blockedSenders: [],
+        },
+        { mailboxId: MailboxId.unchecked("title.toggle.02") },
+      );
+      await repo.save(feed);
+
+      const form = new FormData();
+      form.append("title", "Title Toggle Feed");
+      form.append("sender_in_title", "true");
+      const post = await request(`/admin/feeds/${feedId.value}/edit`, {
+        method: "POST",
+        headers: {
+          Cookie: authCookie,
+          Origin: "https://test.getmynews.app",
+        },
+        body: form,
+      });
+      expect(post.status).toBe(302);
+
+      const cfg = await repo.getConfig(feedId);
+      expect(cfg?.sender_in_title).toBe(true);
+
+      const editPage = await request(`/admin/feeds/${feedId.value}/edit`, {
+        headers: { Cookie: authCookie },
+      });
+      expect(await editPage.text()).toContain("checked");
+    });
+
+    it("clears the toggle when the checkbox is omitted (unchecked)", async () => {
+      const authCookie = await loginAndGetCookie();
+      const repo = FeedRepository.from(mockEnv as unknown as Env);
+      const feedId = FeedId.generate();
+      const feed = Feed.create(
+        feedId,
+        {
+          title: "Title Toggle Feed",
+          language: "en",
+          senderInTitle: true,
+          allowedSenders: [],
+          blockedSenders: [],
+        },
+        { mailboxId: MailboxId.unchecked("title.toggle.03") },
+      );
+      await repo.save(feed);
+
+      const form = new FormData();
+      form.append("title", "Title Toggle Feed");
+      // No sender_in_title field ⇒ unchecked.
+      const post = await request(`/admin/feeds/${feedId.value}/edit`, {
+        method: "POST",
+        headers: {
+          Cookie: authCookie,
+          Origin: "https://test.getmynews.app",
+        },
+        body: form,
+      });
+      expect(post.status).toBe(302);
+
+      const cfg = await repo.getConfig(feedId);
+      expect(cfg?.sender_in_title).toBe(false);
+    });
+  });
 });
diff --git a/src/routes/admin/feeds.tsx b/src/routes/admin/feeds.tsx
index 06a9fa4..9214b03 100644
--- a/src/routes/admin/feeds.tsx
+++ b/src/routes/admin/feeds.tsx
@@ -269,6 +269,23 @@ feedsRouter.get("/:feedId/edit", async (c) => {
               </small>
             </div>
 
+            <div class="form-group">
+              <label class="checkbox-label">
+                <input
+                  type="checkbox"
+                  name="sender_in_title"
+                  value="true"
+                  checked={feedConfig.sender_in_title ?? false}
+                  disabled={isExpired}
+                />
+                Show sender in entry titles
+              </label>
+              <small>
+                Render each entry's title as <code>[Sender] Subject</code> for
+                at-a-glance scanning in your reader.
+              </small>
+            </div>
+
             <div class="form-group">
               <label for="lifetime_hours">Lifetime (hours)</label>
               <input
@@ -322,6 +339,7 @@ feedsRouter.post("/:feedId/edit", async (c) => {
     const blockedSenders = parseAllowedSenders(
       formData.get("blocked_senders")?.toString() || "",
     );
+    const senderInTitle = formData.get("sender_in_title") === "true";
     const lifetimeHoursRaw = formData.get("lifetime_hours")?.toString();
 
     const parsedData = updateFeedSchema.parse({
@@ -338,6 +356,7 @@ feedsRouter.post("/:feedId/edit", async (c) => {
       language: parsedData.language,
       allowedSenders: parsedData.allowedSenders,
       blockedSenders: parsedData.blockedSenders,
+      senderInTitle,
       lifetimeHours: lifetimeHoursRaw
         ? parseInt(lifetimeHoursRaw, 10)
         : undefined,
diff --git a/src/routes/api/api.test.ts b/src/routes/api/api.test.ts
index c8fed28..bf97c99 100644
--- a/src/routes/api/api.test.ts
+++ b/src/routes/api/api.test.ts
@@ -143,6 +143,40 @@ describe("REST API (/api/v1)", () => {
       expect(afterList.feeds.map((f) => f.id)).not.toContain(created.id);
     });
 
+    it("defaults senderInTitle to false and lets it be set on create and update", async () => {
+      const createRes = await request("/api/v1/feeds", {
+        method: "POST",
+        headers: { ...authHeaders, "Content-Type": "application/json" },
+        body: JSON.stringify({ title: "Title Feed" }),
+      });
+      const created = (await createRes.json()) as {
+        id: string;
+        senderInTitle: boolean;
+      };
+      expect(created.senderInTitle).toBe(false);
+
+      const setRes = await request("/api/v1/feeds", {
+        method: "POST",
+        headers: { ...authHeaders, "Content-Type": "application/json" },
+        body: JSON.stringify({ title: "Prefixed Feed", senderInTitle: true }),
+      });
+      const set = (await setRes.json()) as {
+        id: string;
+        senderInTitle: boolean;
+      };
+      expect(set.senderInTitle).toBe(true);
+
+      const patchRes = await request(`/api/v1/feeds/${set.id}`, {
+        method: "PATCH",
+        headers: { ...authHeaders, "Content-Type": "application/json" },
+        body: JSON.stringify({ senderInTitle: false }),
+      });
+      expect(patchRes.status).toBe(200);
+      expect(
+        (await patchRes.json()) as { senderInTitle: boolean },
+      ).toMatchObject({ senderInTitle: false });
+    });
+
     it("returns 400 for an invalid create body", async () => {
       const res = await request("/api/v1/feeds", {
         method: "POST",
diff --git a/src/routes/api/index.ts b/src/routes/api/index.ts
index 8a93a66..2131914 100644
--- a/src/routes/api/index.ts
+++ b/src/routes/api/index.ts
@@ -59,6 +59,7 @@ function toFeed(
     language: config.language,
     allowedSenders: config.allowed_senders ?? [],
     blockedSenders: config.blocked_senders ?? [],
+    senderInTitle: config.sender_in_title ?? false,
     createdAt: config.created_at,
     updatedAt: config.updated_at,
     expiresAt: config.expires_at,
@@ -152,6 +153,7 @@ apiApp.openapi(
       language: body.language,
       allowedSenders: normalizeSenders(body.allowedSenders) ?? [],
       blockedSenders: normalizeSenders(body.blockedSenders) ?? [],
+      senderInTitle: body.senderInTitle,
       lifetimeHours: body.lifetimeHours,
     });
     return c.json(toFeed(feedId, config, 0, env), 201);
@@ -217,6 +219,7 @@ apiApp.openapi(
       language: body.language,
       allowedSenders: normalizeSenders(body.allowedSenders),
       blockedSenders: normalizeSenders(body.blockedSenders),
+      senderInTitle: body.senderInTitle,
       lifetimeHours: body.lifetimeHours,
     });
     if (result.status === "not_found")
diff --git a/src/routes/api/schemas.ts b/src/routes/api/schemas.ts
index 82d6ddf..3e7f329 100644
--- a/src/routes/api/schemas.ts
+++ b/src/routes/api/schemas.ts
@@ -39,6 +39,10 @@ export const FeedCreateSchema = z
     language: z.string().optional().default("en"),
     allowedSenders: z.array(z.string()).optional().default([]),
     blockedSenders: z.array(z.string()).optional().default([]),
+    senderInTitle: z.boolean().optional().openapi({
+      description:
+        "Render entry titles as `[Sender] Subject` in the feed output.",
+    }),
     lifetimeHours: z.number().int().positive().optional().openapi({
       description:
         "Hours until the feed expires. Ignored when the server enforces a fixed FEED_TTL_HOURS.",
@@ -53,6 +57,10 @@ export const FeedUpdateSchema = z
     language: z.string().optional(),
     allowedSenders: z.array(z.string()).optional(),
     blockedSenders: z.array(z.string()).optional(),
+    senderInTitle: z.boolean().optional().openapi({
+      description:
+        "Render entry titles as `[Sender] Subject` in the feed output.",
+    }),
     lifetimeHours: z.number().int().positive().optional().openapi({
       description: "Reset the feed's lifetime to this many hours from now.",
     }),
@@ -83,6 +91,7 @@ export const FeedSchema = z
     language: z.string(),
     allowedSenders: z.array(z.string()),
     blockedSenders: z.array(z.string()),
+    senderInTitle: z.boolean(),
     createdAt: z.number(),
     updatedAt: z.number().optional(),
     expiresAt: z.number().optional(),
diff --git a/src/styles/components.css b/src/styles/components.css
index c172f3c..4742812 100644
--- a/src/styles/components.css
+++ b/src/styles/components.css
@@ -295,6 +295,19 @@ label {
   color: var(--color-text-secondary);
 }
 
+.checkbox-label {
+  display: flex;
+  align-items: center;
+  gap: var(--spacing-sm);
+  cursor: pointer;
+}
+
+.checkbox-label input[type="checkbox"] {
+  width: auto;
+  margin: 0;
+  cursor: pointer;
+}
+
 input[type="text"],
 input[type="email"],
 input[type="search"],
diff --git a/src/types/index.ts b/src/types/index.ts
index 1e59359..f2e8a8d 100644
--- a/src/types/index.ts
+++ b/src/types/index.ts
@@ -49,6 +49,8 @@ export interface FeedConfig {
   blocked_senders?: string[];
   language: string;
   author?: string;
+  // When true, entry titles in the feed output are rendered as `[Sender] Subject`.
+  sender_in_title?: boolean;
   created_at: number;
   updated_at?: number;
   expires_at?: number; // Unix timestamp ms — present when a TTL is configured