diff --git a/lastleg-service/src/main/java/com/baiyue/lastleg/service/LastlegOrderNoGenerator.java b/lastleg-service/src/main/java/com/baiyue/lastleg/service/LastlegOrderNoGenerator.java
index fb34ba751..9c6f8cb0f 100644
--- a/lastleg-service/src/main/java/com/baiyue/lastleg/service/LastlegOrderNoGenerator.java
+++ b/lastleg-service/src/main/java/com/baiyue/lastleg/service/LastlegOrderNoGenerator.java
@@ -47,6 +47,11 @@ public class LastlegOrderNoGenerator {
         // Return numbers are independent business identifiers, not truncated database IDs.
         // Keep every UUID bit; the longest result (RETU + 25 base-36 digits) fits VARCHAR(32).
         if (returnPrefix != null) return returnPrefix + "-" + encodeReturnUuid(UUID.randomUUID());
+        // Transfer numbers also identify synthetic inbound events globally. Truncating
+        // a database ID to six digits can collide between unrelated fresh transfers.
+        if ("TRANSFER".equals(code) || "WAREHOUSE_TRANSFER".equals(code)) {
+            return "WT-" + encodeReturnUuid(UUID.randomUUID());
+        }
         String type = normalizeType(businessType);
         return type + "-" + warehouseCode(warehouse) + "-"
             + LocalDate.now().format(DateTimeFormatter.BASIC_ISO_DATE) + "-"
diff --git a/lastleg-service/src/test/java/com/baiyue/lastleg/service/LastlegOrderNoGeneratorTest.java b/lastleg-service/src/test/java/com/baiyue/lastleg/service/LastlegOrderNoGeneratorTest.java
index 94b6c5316..8bef1431f 100644
--- a/lastleg-service/src/test/java/com/baiyue/lastleg/service/LastlegOrderNoGeneratorTest.java
+++ b/lastleg-service/src/test/java/com/baiyue/lastleg/service/LastlegOrderNoGeneratorTest.java
@@ -81,4 +81,14 @@ class LastlegOrderNoGeneratorTest {
         assertTrue(value.matches("OB-LAX-\\d{8}-000123"), value);
         assertTrue(value.length() <= 24);
     }
+
+    @Test void transferNumbersDoNotCollideWhenDatabaseIdSuffixesRepeat() {
+        String first = generator.next("TRANSFER", "warehouse-LAX-01", 123L);
+        String second = generator.next("TRANSFER", "warehouse-LAX-01", 1_000_123L);
+        String repeatedId = generator.next("WAREHOUSE_TRANSFER", "warehouse-LAX-01", 123L);
+        assertTrue(first.matches("WT-[0-9A-Z]{25}"), first);
+        assertTrue(first.length() <= 32);
+        assertNotEquals(first, second);
+        assertNotEquals(first, repeatedId);
+    }
 }
diff --git a/lastleg-service/src/test/java/com/baiyue/lastleg/transfer/service/WarehouseTransferServiceTest.java b/lastleg-service/src/test/java/com/baiyue/lastleg/transfer/service/WarehouseTransferServiceTest.java
index a0015ff55..53b05d619 100644
--- a/lastleg-service/src/test/java/com/baiyue/lastleg/transfer/service/WarehouseTransferServiceTest.java
+++ b/lastleg-service/src/test/java/com/baiyue/lastleg/transfer/service/WarehouseTransferServiceTest.java
@@ -231,7 +231,7 @@ class WarehouseTransferServiceTest {
         ReflectionTestUtils.setField(service, "relabelService", relabelService);
         ReflectionTestUtils.setField(service, "objectMapper", new ObjectMapper().findAndRegisterModules());
         lenient().when(orderNoGenerator.next(anyString(), any(), anyLong()))
-            .thenReturn("WT-WH-20260901-000001");
+            .thenReturn("WT-0000000000000000000000001");
         lenient().when(inventoryAllocations.selectList(any())).thenReturn(List.of());
         lenient().when(transferReceipts.selectList(any())).thenReturn(List.of());
         lenient().when(transferCartons.listOrder(anyString(), anyLong())).thenReturn(List.of());
@@ -386,7 +386,7 @@ class WarehouseTransferServiceTest {
         assertEquals(WarehouseTransferService.ORDER_TYPE, tailOrder.getValue().getOrderType());
         assertEquals(WarehouseTransferService.DRAFT, tailOrder.getValue().getCurrentStatus());
         assertEquals("WAREHOUSE_TRANSFER:DRAFT;RELABEL:PENDING_BINDING", tailOrder.getValue().getSubOrderStatus());
-        assertTrue(tailOrder.getValue().getOrderNo().matches("WT-WH-\\d{8}-\\d{6}"));
+        assertTrue(tailOrder.getValue().getOrderNo().matches("WT-[0-9A-Z]{25}"));
         assertNull(tailOrder.getValue().getTransferWarehouseId());
         verify(sourceOrders).insert(any(WarehouseTransferSourceOrder.class));
         verify(relabelApplications, never()).insert(any(RelabelApplication.class));
@@ -544,7 +544,7 @@ class WarehouseTransferServiceTest {
         assertEquals(List.of(1, 2, 3, 4, 5), cartons.getAllValues().stream()
             .map(WarehouseTransferCarton::getCartonIndex).toList());
         assertTrue(cartons.getAllValues().stream().allMatch(value -> value.getCartonMark()
-            .matches("WT-WH-\\d{8}-\\d{6}#5-[1-5]")));
+            .matches("WT-[0-9A-Z]{25}#5-[1-5]")));
     }
 
     @Test