diff --git a/src/hooks/useTailStream.test.ts b/src/hooks/useTailStream.test.ts
index 5247e4b..4664247 100644
--- a/src/hooks/useTailStream.test.ts
+++ b/src/hooks/useTailStream.test.ts
@@ -15,7 +15,7 @@ import {
 } from "vitest";
 import { useTailStream } from "./useTailStream";
 import { useTailStore } from "@/store/tail-store";
-import type { Claim } from "@/types";
+import type { Ack, Claim, Ta1Ack } from "@/types";
 import type { TailEvent } from "@/lib/tail-stream";
 
 // ---------------------------------------------------------------------------
@@ -204,6 +204,34 @@ function makeClaim(id: string, patientName: string): Claim {
   };
 }
 
+function makeAck(id: number, sourceBatchId: string): Ack {
+  return {
+    id,
+    sourceBatchId,
+    acceptedCount: 1,
+    rejectedCount: 0,
+    receivedCount: 1,
+    ackCode: "A",
+    parsedAt: "2026-07-02T12:00:00Z",
+    patientControlNumber: `PCN-${id}`,
+  };
+}
+
+function makeTa1Ack(id: number, controlNumber: string): Ta1Ack {
+  return {
+    id,
+    controlNumber,
+    ackCode: "A",
+    noteCode: "000",
+    interchangeDate: "2026-07-02",
+    interchangeTime: "1200",
+    senderId: "S",
+    receiverId: "R",
+    sourceBatchId: `TA1-${id}`,
+    parsedAt: "2026-07-02T12:00:00Z",
+  };
+}
+
 describe("useTailStream", () => {
   beforeEach(() => {
     mockStreamTail.mockReset();
@@ -212,6 +240,8 @@ describe("useTailStream", () => {
     useTailStore.getState().reset("claims");
     useTailStore.getState().reset("remittances");
     useTailStore.getState().reset("activity");
+    useTailStore.getState().reset("acks");
+    useTailStore.getState().reset("ta1_acks");
   });
 
   afterEach(() => {
@@ -400,4 +430,60 @@ describe("useTailStream", () => {
 
     unmount();
   });
+
+  // -------------------------------------------------------------------------
+  // SP25: the Acks page mounts useTailStream("acks") and
+  // useTailStream("ta1_acks"). The dispatcher must route their item events
+  // into the matching store slices.
+  // -------------------------------------------------------------------------
+
+  it("test_acks_item_event_lands_in_acks_slice", async () => {
+    const { ctrls } = trackCalls();
+    const { unmount } = renderHook(() => useTailStream("acks"));
+
+    await waitFor(() => ctrls.length === 1);
+    ctrls[0].push({ type: "snapshot_end", data: { count: 0 } });
+    await waitFor(() => useTailStore.getState().acks !== undefined);
+
+    ctrls[0].push({
+      type: "item",
+      data: makeAck(42, "BATCH-LIVE"),
+    });
+
+    await waitFor(
+      () => useTailStore.getState().acks["42"] !== undefined,
+    );
+    const stored = useTailStore.getState().acks["42"];
+    expect(stored).toBeDefined();
+    expect(stored?.sourceBatchId).toBe("BATCH-LIVE");
+    // The Acks page must NOT see this row in the claims slice.
+    expect(useTailStore.getState().claims["42"]).toBeUndefined();
+
+    unmount();
+  });
+
+  it("test_ta1_acks_item_event_lands_in_ta1_acks_slice", async () => {
+    const { ctrls } = trackCalls();
+    const { unmount } = renderHook(() => useTailStream("ta1_acks"));
+
+    await waitFor(() => ctrls.length === 1);
+    ctrls[0].push({ type: "snapshot_end", data: { count: 0 } });
+    await waitFor(() => useTailStore.getState().ta1Acks !== undefined);
+
+    ctrls[0].push({
+      type: "item",
+      data: makeTa1Ack(7, "000000007"),
+    });
+
+    await waitFor(
+      () => useTailStore.getState().ta1Acks["7"] !== undefined,
+    );
+    const stored = useTailStore.getState().ta1Acks["7"];
+    expect(stored).toBeDefined();
+    expect(stored?.controlNumber).toBe("000000007");
+    // Must NOT bleed into the acks slice — keyed by id, separate dicts.
+    expect(useTailStore.getState().acks["7"]).toBeUndefined();
+
+    unmount();
+  });
 });
diff --git a/src/hooks/useTailStream.ts b/src/hooks/useTailStream.ts
index 5394c22..5494f1e 100644
--- a/src/hooks/useTailStream.ts
+++ b/src/hooks/useTailStream.ts
@@ -27,7 +27,7 @@
 import { useCallback, useEffect, useRef, useState } from "react";
 import { streamTail, type TailResource } from "@/lib/tail-stream";
 import { useTailStore } from "@/store/tail-store";
-import type { Activity, Claim, Remittance } from "@/types";
+import type { Ack, Activity, Claim, Remittance, Ta1Ack } from "@/types";
 
 export type TailStatus =
   | "connecting"
@@ -74,6 +74,17 @@ function dispatch(resource: TailResource, data: unknown): void {
     case "activity":
       store.addActivity(data as Activity);
       break;
+    // SP25: the Acks page opens two streams — one per ack flavor —
+    // and the live event payloads are the same shape as the list
+    // endpoint (to_ui_ack / to_ui_ta1_ack in store/ui.py). The first
+    // write wins, so a snapshot replay on reconnect won't trample
+    // the canonical row.
+    case "acks":
+      store.addAck(data as Ack);
+      break;
+    case "ta1_acks":
+      store.addTa1Ack(data as Ta1Ack);
+      break;
   }
 }