diff --git a/web/src/pages/CreateLocationPage.tsx b/web/src/pages/CreateLocationPage.tsx
index e6a4748..ad1f7e5 100644
--- a/web/src/pages/CreateLocationPage.tsx
+++ b/web/src/pages/CreateLocationPage.tsx
@@ -3,6 +3,7 @@ import { useNavigate } from 'react-router-dom'
 import { inventory } from '@/api/client'
 import { PageHeader } from '@/components/PageHeader'
 import { ErrorBox } from '@/components/ErrorBox'
+import { DynamicExtFields } from '@/components/DynamicExtFields'
 
 const LOCATION_TYPES = ['WAREHOUSE', 'BIN', 'VIRTUAL'] as const
 
@@ -11,6 +12,7 @@ export function CreateLocationPage() {
   const [code, setCode] = useState('')
   const [name, setName] = useState('')
   const [type, setType] = useState<string>('WAREHOUSE')
+  const [ext, setExt] = useState<Record<string, unknown>>({})
   const [submitting, setSubmitting] = useState(false)
   const [error, setError] = useState<Error | null>(null)
 
@@ -19,7 +21,8 @@ export function CreateLocationPage() {
     setError(null)
     setSubmitting(true)
     try {
-      await inventory.createLocation({ code, name, type })
+      const extPayload = Object.keys(ext).length > 0 ? ext : undefined
+      await inventory.createLocation({ code, name, type, ...(extPayload ? { ext: extPayload } : {}) })
       navigate('/locations')
     } catch (err: unknown) {
       setError(err instanceof Error ? err : new Error(String(err)))
@@ -53,6 +56,11 @@ export function CreateLocationPage() {
             {LOCATION_TYPES.map((t) => <option key={t} value={t}>{t}</option>)}
           </select>
         </div>
+        <DynamicExtFields
+          entityName="Location"
+          values={ext}
+          onChange={(k, v) => setExt((prev) => ({ ...prev, [k]: v }))}
+        />
         {error && <ErrorBox error={error} />}
         <button type="submit" className="btn-primary" disabled={submitting}>
           {submitting ? 'Creating...' : 'Create Location'}
diff --git a/web/src/pages/CreatePurchaseOrderPage.tsx b/web/src/pages/CreatePurchaseOrderPage.tsx
index a2fc1de..4973dac 100644
--- a/web/src/pages/CreatePurchaseOrderPage.tsx
+++ b/web/src/pages/CreatePurchaseOrderPage.tsx
@@ -4,6 +4,7 @@ import { catalog, partners, purchaseOrders } from '@/api/client'
 import type { Item, Partner } from '@/types/api'
 import { PageHeader } from '@/components/PageHeader'
 import { ErrorBox } from '@/components/ErrorBox'
+import { DynamicExtFields } from '@/components/DynamicExtFields'
 
 interface LineInput {
   itemCode: string
@@ -20,6 +21,7 @@ export function CreatePurchaseOrderPage() {
   const [lines, setLines] = useState<LineInput[]>([{ itemCode: '', quantity: '', unitPrice: '' }])
   const [items, setItems] = useState<Item[]>([])
   const [supplierList, setSupplierList] = useState<Partner[]>([])
+  const [ext, setExt] = useState<Record<string, unknown>>({})
   const [submitting, setSubmitting] = useState(false)
   const [error, setError] = useState<Error | null>(null)
 
@@ -51,6 +53,7 @@ export function CreatePurchaseOrderPage() {
     setError(null)
     setSubmitting(true)
     try {
+      const extPayload = Object.keys(ext).length > 0 ? ext : undefined
       const created = await purchaseOrders.create({
         code, partnerCode, currencyCode,
         orderDate: new Date().toISOString().slice(0, 10),
@@ -62,6 +65,7 @@ export function CreatePurchaseOrderPage() {
           unitPrice: Number(l.unitPrice),
           currencyCode,
         })),
+        ...(extPayload ? { ext: extPayload } : {}),
       })
       navigate(`/purchase-orders/${created.id}`)
     } catch (err: unknown) {
@@ -128,6 +132,11 @@ export function CreatePurchaseOrderPage() {
           </div>
         </div>
 
+        <DynamicExtFields
+          entityName="PurchaseOrder"
+          values={ext}
+          onChange={(k, v) => setExt((prev) => ({ ...prev, [k]: v }))}
+        />
         {error && <ErrorBox error={error} />}
         <button type="submit" className="btn-primary" disabled={submitting}>
           {submitting ? 'Creating...' : 'Create Purchase Order'}
diff --git a/web/src/pages/CreateSalesOrderPage.tsx b/web/src/pages/CreateSalesOrderPage.tsx
index 6014e1c..bdbe7cc 100644
--- a/web/src/pages/CreateSalesOrderPage.tsx
+++ b/web/src/pages/CreateSalesOrderPage.tsx
@@ -4,6 +4,7 @@ import { catalog, partners, salesOrders } from '@/api/client'
 import type { Item, Partner } from '@/types/api'
 import { PageHeader } from '@/components/PageHeader'
 import { ErrorBox } from '@/components/ErrorBox'
+import { DynamicExtFields } from '@/components/DynamicExtFields'
 
 interface LineInput {
   itemCode: string
@@ -21,6 +22,7 @@ export function CreateSalesOrderPage() {
   ])
   const [items, setItems] = useState<Item[]>([])
   const [partnerList, setPartnerList] = useState<Partner[]>([])
+  const [ext, setExt] = useState<Record<string, unknown>>({})
   const [submitting, setSubmitting] = useState(false)
   const [error, setError] = useState<Error | null>(null)
 
@@ -52,6 +54,7 @@ export function CreateSalesOrderPage() {
     setError(null)
     setSubmitting(true)
     try {
+      const extPayload = Object.keys(ext).length > 0 ? ext : undefined
       const created = await salesOrders.create({
         code,
         partnerCode,
@@ -64,7 +67,8 @@ export function CreateSalesOrderPage() {
           unitPrice: Number(l.unitPrice),
           currencyCode,
         })),
-      })
+        ...(extPayload ? { ext: extPayload } : {}),
+      } as Parameters<typeof salesOrders.create>[0])
       navigate(`/sales-orders/${created.id}`)
     } catch (err: unknown) {
       setError(err instanceof Error ? err : new Error(String(err)))
@@ -177,6 +181,12 @@ export function CreateSalesOrderPage() {
           </div>
         </div>
 
+        <DynamicExtFields
+          entityName="SalesOrder"
+          values={ext}
+          onChange={(k, v) => setExt((prev) => ({ ...prev, [k]: v }))}
+        />
+
         {error && <ErrorBox error={error} />}
 
         <div className="flex items-center gap-3 pt-2">
diff --git a/web/src/pages/CreateWorkOrderPage.tsx b/web/src/pages/CreateWorkOrderPage.tsx
index 05afd25..db5ce3b 100644
--- a/web/src/pages/CreateWorkOrderPage.tsx
+++ b/web/src/pages/CreateWorkOrderPage.tsx
@@ -4,6 +4,7 @@ import { catalog, inventory, production } from '@/api/client'
 import type { Item, Location } from '@/types/api'
 import { PageHeader } from '@/components/PageHeader'
 import { ErrorBox } from '@/components/ErrorBox'
+import { DynamicExtFields } from '@/components/DynamicExtFields'
 
 interface BomLine { itemCode: string; quantityPerUnit: string; sourceLocationCode: string }
 interface OpLine { operationCode: string; workCenter: string; standardMinutes: string }
@@ -18,6 +19,7 @@ export function CreateWorkOrderPage() {
   const [ops, setOps] = useState<OpLine[]>([])
   const [items, setItems] = useState<Item[]>([])
   const [locations, setLocations] = useState<Location[]>([])
+  const [ext, setExt] = useState<Record<string, unknown>>({})
   const [submitting, setSubmitting] = useState(false)
   const [error, setError] = useState<Error | null>(null)
 
@@ -47,6 +49,7 @@ export function CreateWorkOrderPage() {
     setError(null)
     setSubmitting(true)
     try {
+      const extPayload = Object.keys(ext).length > 0 ? ext : undefined
       const created = await production.createWorkOrder({
         code, outputItemCode,
         outputQuantity: Number(outputQuantity),
@@ -61,6 +64,7 @@ export function CreateWorkOrderPage() {
           workCenter: o.workCenter,
           standardMinutes: Number(o.standardMinutes),
         })),
+        ...(extPayload ? { ext: extPayload } : {}),
       })
       navigate(`/work-orders/${created.id}`)
     } catch (err: unknown) {
@@ -160,6 +164,11 @@ export function CreateWorkOrderPage() {
           </div>
         </div>
 
+        <DynamicExtFields
+          entityName="WorkOrder"
+          values={ext}
+          onChange={(k, v) => setExt((prev) => ({ ...prev, [k]: v }))}
+        />
         {error && <ErrorBox error={error} />}
         <button type="submit" className="btn-primary" disabled={submitting}>
           {submitting ? 'Creating...' : 'Create Work Order'}