diff --git a/src/admin/pages/InvoiceDetail.tsx b/src/admin/pages/InvoiceDetail.tsx
index ac62cc7..ecbf356 100644
--- a/src/admin/pages/InvoiceDetail.tsx
+++ b/src/admin/pages/InvoiceDetail.tsx
@@ -634,6 +634,20 @@ export default function InvoiceDetail() {
     };
   }, []);
 
+  // After an in-place draft→issued finalize, the one-shot hydration effect below
+  // (gated by dataReady) won't re-run, so the freshly-assigned number from the
+  // refetched query is mirrored into the local field here (matches the
+  // issued-order page's po_number resync).
+  useEffect(() => {
+    if (
+      isEdit &&
+      invoice?.invoice_number &&
+      invoice.invoice_number !== invoiceNumber
+    ) {
+      setInvoiceNumber(invoice.invoice_number);
+    }
+  }, [isEdit, invoice?.invoice_number, invoiceNumber]);
+
   // ─── Sync query data to form state ───
 
   // Edit mode: populate form from invoice data