diff --git a/lib/auto-trade.ts b/lib/auto-trade.ts
index 8a31288..afe8f8d 100644
--- a/lib/auto-trade.ts
+++ b/lib/auto-trade.ts
@@ -50,24 +50,49 @@ function mapFirmConfig(firm: FirmWithAccounts): FirmConfig {
 
 // ── helpers ───────────────────────────────────────────────────────────────────
 
-/** Returns true during the 3:00 PM – 4:59 PM Central no-trade window. */
+/**
+ * Returns true when CME futures markets are closed.
+ * CME hours: Sunday 5:00 PM – Friday 4:00 PM Central, with a daily halt 4:00–5:00 PM.
+ * So we block trading when:
+ *   - It's 3:00 PM – 4:59 PM Central (stop early + daily halt)
+ *   - It's Saturday (all day)
+ *   - It's Sunday before 5:00 PM Central
+ *   - It's Friday after 3:00 PM Central
+ */
 function isInNoTradeWindow(): boolean {
-    const hour = parseInt(
-        new Intl.DateTimeFormat('en-US', {
-            hour: 'numeric',
-            hour12: false,
-            timeZone: 'America/Chicago',
-        }).format(new Date()),
-        10
-    );
-    return hour >= 15 && hour < 17;
+    const now = new Date();
+    const centralTime = new Intl.DateTimeFormat('en-US', {
+        hour: 'numeric',
+        hour12: false,
+        timeZone: 'America/Chicago',
+    });
+    const centralDay = new Intl.DateTimeFormat('en-US', {
+        weekday: 'short',
+        timeZone: 'America/Chicago',
+    });
+    const hour = parseInt(centralTime.format(now), 10);
+    const day = centralDay.format(now); // "Sun", "Mon", ... "Sat"
+
+    // Saturday — market closed all day
+    if (day === 'Sat') return true;
+
+    // Sunday — market opens at 5 PM Central
+    if (day === 'Sun' && hour < 17) return true;
+
+    // Friday — stop trading after 3 PM Central
+    if (day === 'Fri' && hour >= 15) return true;
+
+    // Mon–Thu: stop trading after 3 PM Central (market halts at 4 PM, reopens 5 PM)
+    if (hour >= 15 && hour < 17) return true;
+
+    return false;
 }
 
 // ── core trade logic ──────────────────────────────────────────────────────────
 
 export async function runTrade(action: 'Buy' | 'Sell' | 'Random', symbol: string) {
     if (isInNoTradeWindow()) {
-        console.log('[auto-trade] no-trade window active (3–5 PM Central) — skipping');
+        console.log('[auto-trade] CME market closed — skipping');
         return [];
     }
     // Resolve 'Random' symbol once per batch so all accounts trade the same symbol