diff --git a/backend/app/api/routers/orders.py b/backend/app/api/routers/orders.py
index e39cac8..e3011c8 100644
--- a/backend/app/api/routers/orders.py
+++ b/backend/app/api/routers/orders.py
@@ -1097,6 +1097,32 @@ async def dispatch_single_line_render(
     return {"dispatched": True, "line_id": str(line.id)}
 
 
+class BatchMaterialOverrideBody(BaseModel):
+    material_override: str | None = None
+
+
+@router.post("/{order_id}/batch-material-override")
+async def batch_material_override(
+    order_id: uuid.UUID,
+    body: BatchMaterialOverrideBody,
+    user: User = Depends(require_admin_or_pm),
+    db: AsyncSession = Depends(get_db),
+):
+    """Set material_override on ALL lines of an order at once."""
+    result = await db.execute(select(Order).where(Order.id == order_id))
+    if not result.scalar_one_or_none():
+        raise HTTPException(404, detail="Order not found")
+
+    from sqlalchemy import update as sql_update
+    res = await db.execute(
+        sql_update(OrderLine)
+        .where(OrderLine.order_id == order_id)
+        .values(material_override=body.material_override)
+    )
+    await db.commit()
+    return {"updated": res.rowcount, "material_override": body.material_override}
+
+
 class PatchLineBody(BaseModel):
     material_override: str | None = None
 
diff --git a/frontend/src/api/orders.ts b/frontend/src/api/orders.ts
index fb83dcd..5271422 100644
--- a/frontend/src/api/orders.ts
+++ b/frontend/src/api/orders.ts
@@ -244,6 +244,14 @@ export async function dispatchLineRender(orderId: string, lineId: string) {
   return res.data
 }
 
+export async function batchMaterialOverride(orderId: string, materialOverride: string | null) {
+  const res = await api.post<{ updated: number; material_override: string | null }>(
+    `/orders/${orderId}/batch-material-override`,
+    { material_override: materialOverride }
+  )
+  return res.data
+}
+
 export async function patchOrderLine(orderId: string, lineId: string, data: { material_override?: string | null }) {
   const res = await api.patch<{ updated: boolean; line_id: string }>(
     `/orders/${orderId}/lines/${lineId}`,
diff --git a/frontend/src/pages/OrderDetail.tsx b/frontend/src/pages/OrderDetail.tsx
index b044ae1..7447e50 100644
--- a/frontend/src/pages/OrderDetail.tsx
+++ b/frontend/src/pages/OrderDetail.tsx
@@ -12,7 +12,7 @@ import {
   XCircle, RotateCw, Info,
 } from 'lucide-react'
 import { toast } from 'sonner'
-import { getOrder, submitOrder, deleteOrder, unlinkCadFile, regenerateItemThumbnail, patchOrderItem, removeOrderLine, dispatchRenders, cancelLineRender, dispatchLineRender, cancelOrderRenders, splitMissingStep, generateLinesFromItems, downloadOrderRenders, rejectOrder, resubmitOrder, rejectOrderLine, patchOrderLine } from '../api/orders'
+import { getOrder, submitOrder, deleteOrder, unlinkCadFile, regenerateItemThumbnail, patchOrderItem, removeOrderLine, dispatchRenders, cancelLineRender, dispatchLineRender, cancelOrderRenders, splitMissingStep, generateLinesFromItems, downloadOrderRenders, rejectOrder, resubmitOrder, rejectOrderLine, patchOrderLine, batchMaterialOverride } from '../api/orders'
 import { checkOrderMaterials, listMaterials, type UnmappedMaterial, type Material } from '../api/materials'
 import UnmappedMaterialsDialog from '../components/orders/UnmappedMaterialsDialog'
 import type { OrderItem, OrderLine } from '../api/orders'
@@ -128,6 +128,18 @@ export default function OrderDetailPage() {
     }
   }
 
+  const { data: matList } = useQuery({ queryKey: ['materials'], queryFn: listMaterials })
+  const orderLibMats = (matList ?? []).filter((m: Material) => m.schaeffler_code !== null).sort((a: Material, b: Material) => a.name.localeCompare(b.name))
+
+  const batchOverrideMut = useMutation({
+    mutationFn: (val: string | null) => batchMaterialOverride(id!, val),
+    onSuccess: (data) => {
+      toast.success(`Material override ${data.material_override ? 'set' : 'cleared'} on ${data.updated} lines`)
+      qc.invalidateQueries({ queryKey: ['order', id] })
+    },
+    onError: (e: any) => toast.error(e.response?.data?.detail || 'Failed'),
+  })
+
   const cancelAllMut = useMutation({
     mutationFn: () => cancelOrderRenders(id!),
     onSuccess: (data) => {
@@ -606,6 +618,30 @@ export default function OrderDetailPage() {
             </div>
           )}
 
+          {(order.lines?.length ?? 0) > 0 && isPrivileged && (
+            <div className="flex items-center gap-2 mb-2 px-1">
+              <span className="text-xs text-content-muted">Batch material override:</span>
+              <select
+                className="text-xs border border-border-default rounded px-2 py-1"
+                style={{ backgroundColor: 'var(--color-bg-surface)' }}
+                value=""
+                onChange={(e) => {
+                  const val = e.target.value
+                  if (val === '__clear__') batchOverrideMut.mutate(null)
+                  else if (val) batchOverrideMut.mutate(val)
+                }}
+                disabled={batchOverrideMut.isPending}
+              >
+                <option value="">Apply to all lines…</option>
+                <option value="__clear__">— Clear all overrides —</option>
+                {orderLibMats.map((m: Material) => (
+                  <option key={m.id} value={m.name}>{m.name.replace('SCHAEFFLER_', '').replace(/_/g, ' ')}</option>
+                ))}
+              </select>
+              {batchOverrideMut.isPending && <Loader2 size={12} className="animate-spin text-accent" />}
+            </div>
+          )}
+
           {(order.lines?.length ?? 0) > 0 && (
             <div className="overflow-auto">
               <table className="w-full text-sm">