diff --git a/changelog.d/1443-replay-countdown-ten.md b/changelog.d/1443-replay-countdown-ten.md
new file mode 100644
index 000000000..4780f26bf
--- /dev/null
+++ b/changelog.d/1443-replay-countdown-ten.md
@@ -0,0 +1,3 @@
+- Run Space Missions' Replay Ascent countdown from T−10 after the five-second
+  tile hold; the hold ran 10 s and the countdown started at T−05 (Aditya,
+  @Rohilalala, #1443).
diff --git a/src/data/rocketLaunches.test.mjs b/src/data/rocketLaunches.test.mjs
index f94273d4e..38ff4d24c 100644
--- a/src/data/rocketLaunches.test.mjs
+++ b/src/data/rocketLaunches.test.mjs
@@ -445,6 +445,18 @@ test('holds replay at the pad for a real-time countdown independent of replay sp
   assert.ok(liftoff.phaseProgress > 0);
 });
 
+test('runs the five-second tile hold before a full T-10 countdown', () => {
+  const launch = { launchTime: '2026-07-20T10:00:00Z', timeline: [] };
+  // REPLAY ASCENT puts liftoff 5 s (tile hold) + 10 s (countdown) ahead.
+  const hold = replayState(launch, 115000, 12, 28, 5400, 1, 104500, 5);
+  assert.equal(hold.preCountdownActive, true);
+  assert.equal(hold.countdownActive, false);
+  const countdown = replayState(launch, 115000, 12, 28, 5400, 1, 105000, 5);
+  assert.equal(countdown.preCountdownActive, false);
+  assert.equal(countdown.countdownActive, true);
+  assert.equal(countdown.countdownSeconds, 10);
+});
+
 test('hands replay directly from ascent into orbit', () => {
   const launch = { launchTime: '2026-07-20T10:00:00Z', timeline: [] };
   const orbit = replayState(launch, 0, 12, 28, 5400, 1, 16_000);
diff --git a/src/layers/launches/replay.js b/src/layers/launches/replay.js
index 037eff225..364399a5a 100644
--- a/src/layers/launches/replay.js
+++ b/src/layers/launches/replay.js
@@ -139,8 +139,10 @@ export function createReplay({ state: layerState, services, parts, source }) {
       0,
       Number(preCountdownDurationSec) || 0,
     );
+    // The hold precedes the whole countdown; ending it at -hold cut T-10 to T-5.
     const preCountdownActive =
-      preCountdownDuration > 0 && realSecondsSinceStart < -preCountdownDuration;
+      preCountdownDuration > 0 &&
+      realSecondsSinceStart < -REPLAY_COUNTDOWN_DURATION_SEC;
     const countdownActive = realSecondsSinceStart < 0 && !preCountdownActive;
     const countdownSeconds = countdownActive
       ? Math.ceil(-realSecondsSinceStart)