diff --git a/src/components/orders-review-modal.tsx b/src/components/orders-review-modal.tsx
index ffa98c3..0b55c48 100644
--- a/src/components/orders-review-modal.tsx
+++ b/src/components/orders-review-modal.tsx
@@ -135,6 +135,23 @@ export function OrdersReviewModal({
   const [persistedItems, setPersistedItems] = useState(items);
   const [orderNumber, setOrderNumber] = useState(order.order_number);
   const [customerId, setCustomerId] = useState(order.customer);
+
+  // Customer-cascade: when the operator changes the customer, the
+  // Company + Rep labels are derived from the selected customer's
+  // `expand.company` and `expand.rep` relations. The selected
+  // customer's `company` id is also written back to the order on save
+  // (along with the rep's display name). useMemo here — not useEffect
+  // — so the label updates during the same render as the dropdown
+  // change, with no extra renders.
+  const selectedCustomer = useMemo(
+    () => customers.find((c) => c.id === customerId) ?? null,
+    [customers, customerId],
+  );
+  const cascadeCompanyName = selectedCustomer?.expand?.company?.company ?? "";
+  const cascadeRepName =
+    selectedCustomer?.expand?.rep?.name ??
+    selectedCustomer?.expand?.rep?.email ??
+    "";
   const [itemDrafts, setItemDrafts] = useState<Record<string, ItemDraft>>(
     () =>
       Object.fromEntries(
@@ -203,6 +220,21 @@ export function OrdersReviewModal({
   const dirty = useMemo(() => {
     if (orderNumber !== persistedOrder.order_number) return true;
     if (customerId !== persistedOrder.customer) return true;
+    // Company cascades from the selected customer; the modal only
+    // writes it when the new value differs from the persisted one
+    // (matching the save-body guard below).
+    if (
+      selectedCustomer?.company &&
+      selectedCustomer.company !== persistedOrder.company
+    )
+      return true;
+    // Rep cascades as the rep's display name; only considered dirty
+    // when we have a new name AND it differs from the persisted text.
+    if (
+      cascadeRepName &&
+      cascadeRepName !== (persistedOrder.rep ?? "")
+    )
+      return true;
     for (const it of persistedItems) {
       const d = itemDrafts[it.id];
       if (!d) continue;
@@ -230,7 +262,16 @@ export function OrdersReviewModal({
     }
     return false;
     // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [orderNumber, customerId, itemDrafts, persistedOrder.id]);
+  }, [
+    orderNumber,
+    customerId,
+    selectedCustomer?.company,
+    cascadeRepName,
+    itemDrafts,
+    persistedOrder.id,
+    persistedOrder.company,
+    persistedOrder.rep,
+  ]);
 
   // Header totals — read from the live draft state so the totals
   // update as the operator edits. New rows are included with whatever
@@ -343,6 +384,8 @@ export function OrdersReviewModal({
     const body: {
       order_number?: string;
       customer?: string;
+      company?: string;
+      rep?: string;
       items?: Array<{
         id: string;
         quantity?: number | null;
@@ -361,6 +404,25 @@ export function OrdersReviewModal({
 
     if (orderNumber !== persistedOrder.order_number) body.order_number = orderNumber;
     if (customerId !== persistedOrder.customer) body.customer = customerId;
+    // Cascade company from the selected customer. Skipped when the
+    // customer is cleared (we'd then be sending `company: ""` which PB
+    // would 400 on because the orders.company field is required).
+    if (
+      selectedCustomer?.company &&
+      selectedCustomer.company !== persistedOrder.company
+    ) {
+      body.company = selectedCustomer.company;
+    }
+    // Cascade rep from the selected customer's expand.rep. Skipped
+    // when no rep on the new customer (so an order that previously
+    // had a rep keeps it).
+    if (
+      selectedCustomer?.expand?.rep &&
+      cascadeRepName &&
+      cascadeRepName !== (persistedOrder.rep ?? "")
+    ) {
+      body.rep = cascadeRepName;
+    }
 
     const dirtyItems = persistedItems
       .map((it) => {
@@ -685,14 +747,14 @@ export function OrdersReviewModal({
             <div className="space-y-1.5">
               <Label className="text-xs">Company</Label>
               <p className="h-9 inline-flex items-center px-3 rounded-md border bg-muted/30 text-sm">
-                {company?.company || "(unknown)"}
+                {cascadeCompanyName || company?.company || "(unknown)"}
               </p>
             </div>
 
             <div className="space-y-1.5">
               <Label className="text-xs">Rep</Label>
               <p className="h-9 inline-flex items-center px-3 rounded-md border bg-muted/30 text-sm">
-                {persistedOrder.rep || "—"}
+                {cascadeRepName || persistedOrder.rep || "—"}
               </p>
             </div>
           </div>