diff --git a/lib/sp/accountHealth.ts b/lib/sp/accountHealth.ts
new file mode 100644
index 00000000..6362f1a7
--- /dev/null
+++ b/lib/sp/accountHealth.ts
@@ -0,0 +1,35 @@
+// Shared health rules for connected social accounts.
+//
+// Deliberately dependency-free: both the Next server (lib/sp/post.ts) and the
+// Playwright worker (lib/sp/browserPost.ts) import this, and the server must
+// not pull the browser stack into its bundle to read one number.
+
+/**
+ * How many consecutive posting failures an account may rack up before we stop
+ * posting to it and ask the user to reconnect.
+ *
+ * The browser path recognises a dead session by its login wall, but that only
+ * catches a *recognised* failure. When a site redesigns and a selector stops
+ * matching, every attempt fails with a plain timeout instead, nothing flags the
+ * account, and the worker keeps driving a browser at it every cadence tick
+ * forever. One Reddit account reached 2,953 consecutive failures and 0
+ * successes that way, because nothing ever read the counter it was
+ * incrementing.
+ */
+export const MAX_CONSECUTIVE_FAILURES = 10;
+
+/**
+ * Whether this failure should take the account out of rotation.
+ *
+ * `token_expired` is the status the UI already renders as "reconnect", and
+ * account selection only ever picks up `active` rows, so setting it both stops
+ * the retries and tells the user why.
+ */
+export function shouldDisableAccount(args: {
+  consecutiveFailures: number;
+  sessionExpired?: boolean;
+}): boolean {
+  return (
+    Boolean(args.sessionExpired) || args.consecutiveFailures >= MAX_CONSECUTIVE_FAILURES
+  );
+}
diff --git a/lib/sp/browserPost.ts b/lib/sp/browserPost.ts
index e2e748cc..58c95ea2 100644
--- a/lib/sp/browserPost.ts
+++ b/lib/sp/browserPost.ts
@@ -36,6 +36,8 @@ import { reconcilePromo } from "@/lib/promote/reconcilePromo";
 import { pickDefaultSubreddit } from "@/lib/sp/redditSubreddit";
 import { makeCodeWaiter } from "@/lib/sp/verificationChallenge";
 
+import { shouldDisableAccount } from "@/lib/sp/accountHealth";
+
 export async function processBrowserPost(args: {
   postId: string;
   supabase: SupabaseClient<any>;
@@ -219,11 +221,14 @@ async function fail(
     // token_expired so the UI prompts a reconnect (re-export cookies) and stops
     // posting to it until then.
     const sessionExpired = message.startsWith(LOGIN_WALL_PREFIX);
+    const failures = ((acct?.consecutive_failures ?? 0) as number) + 1;
     await supabase
       .from("sp_account")
       .update({
-        consecutive_failures: ((acct?.consecutive_failures ?? 0) as number) + 1,
-        ...(sessionExpired ? { status: "token_expired" } : {}),
+        consecutive_failures: failures,
+        ...(shouldDisableAccount({ consecutiveFailures: failures, sessionExpired })
+          ? { status: "token_expired" }
+          : {}),
       })
       .eq("id", accountId);
   }
diff --git a/lib/sp/post.ts b/lib/sp/post.ts
index 63defd47..38f21504 100644
--- a/lib/sp/post.ts
+++ b/lib/sp/post.ts
@@ -11,6 +11,7 @@ import { graphemeLength } from "./blueskyFacets";
 import { encryptSecret, decryptSecret } from "@/lib/sp/vault";
 import { enqueueBrowserPost } from "@/lib/lx/workerClient";
 import { resolveSubreddit } from "@/lib/sp/redditSubreddit";
+import { shouldDisableAccount } from "@/lib/sp/accountHealth";
 import {
   createBlueskyPost,
   createBlueskySession,
@@ -424,10 +425,17 @@ export async function postViaAccount(args: {
       .from("sp_post")
       .update({ status: "failed", last_error: message })
       .eq("id", row.id);
+    // Same ceiling the browser path applies: an account that has failed this
+    // many times in a row is not going to start working on the next tick, and
+    // retrying it forever just burns quota and hides the real problem.
+    const failures = (account.consecutive_failures ?? 0) + 1;
     await supabase
       .from("sp_account")
       .update({
-        consecutive_failures: (account.consecutive_failures ?? 0) + 1,
+        consecutive_failures: failures,
+        ...(shouldDisableAccount({ consecutiveFailures: failures })
+          ? { status: "token_expired" }
+          : {}),
       })
       .eq("id", account.id);
     await supabase.from("sp_publish_attempt").insert({
diff --git a/tests/sp/account-health.test.ts b/tests/sp/account-health.test.ts
new file mode 100644
index 00000000..03cc7e66
--- /dev/null
+++ b/tests/sp/account-health.test.ts
@@ -0,0 +1,38 @@
+import { describe, it, expect } from "vitest";
+import {
+  MAX_CONSECUTIVE_FAILURES,
+  shouldDisableAccount,
+} from "@/lib/sp/accountHealth";
+
+describe("shouldDisableAccount", () => {
+  it("keeps an account in rotation through a run of transient failures", () => {
+    expect(shouldDisableAccount({ consecutiveFailures: 1 })).toBe(false);
+    expect(
+      shouldDisableAccount({ consecutiveFailures: MAX_CONSECUTIVE_FAILURES - 1 }),
+    ).toBe(false);
+  });
+
+  it("takes it out once the failures stop looking transient", () => {
+    expect(
+      shouldDisableAccount({ consecutiveFailures: MAX_CONSECUTIVE_FAILURES }),
+    ).toBe(true);
+  });
+
+  it("takes it out immediately on a recognised dead session", () => {
+    // A login wall is proof, not a guess — no need to burn ten attempts.
+    expect(shouldDisableAccount({ consecutiveFailures: 1, sessionExpired: true })).toBe(
+      true,
+    );
+  });
+
+  it("would have caught the Reddit account that failed 2953 times", () => {
+    // The regression this exists for: selector timeouts are not login walls, so
+    // nothing flagged the account and the worker retried it for days.
+    expect(shouldDisableAccount({ consecutiveFailures: 2953 })).toBe(true);
+  });
+
+  it("resets are the caller's job — a success zeroes the counter", () => {
+    // Guards the contract the post paths rely on: 0 failures is always healthy.
+    expect(shouldDisableAccount({ consecutiveFailures: 0 })).toBe(false);
+  });
+});