diff --git a/crud.py b/crud.py
index 4fb6f82..dec6007 100644
--- a/crud.py
+++ b/crud.py
@@ -65,6 +65,7 @@ async def create_pay_link(data: CreatePayLinkData) -> PayLink:
         created_at=now,
         updated_at=now,
         disposable=data.disposable if data.disposable is not None else True,
+        verify=data.verify if data.verify is not None else False,
     )
 
     await db.insert("lnurlp.pay_links", link)
diff --git a/migrations.py b/migrations.py
index 2b0e28b..da163b2 100644
--- a/migrations.py
+++ b/migrations.py
@@ -218,3 +218,9 @@ async def m012_add_disposable(db: Connection):
     await db.execute(
         "ALTER TABLE lnurlp.pay_links ADD COLUMN disposable BOOLEAN DEFAULT TRUE"
     )
+
+
+async def m013_add_verify(db: Connection):
+    await db.execute(
+        "ALTER TABLE lnurlp.pay_links ADD COLUMN verify BOOLEAN DEFAULT FALSE"
+    )
diff --git a/models.py b/models.py
index d8e6d6d..f209ccb 100644
--- a/models.py
+++ b/models.py
@@ -35,6 +35,7 @@ class CreatePayLinkData(BaseModel):
     username: str | None = Query(None)
     zaps: bool | None = Query(False)
     disposable: bool | None = Query(True)
+    verify: bool | None = Query(False)
 
 
 class PayLink(BaseModel):
@@ -69,6 +70,7 @@ class PayLink(BaseModel):
     fiat_base_multiplier: int | None = None
 
     disposable: bool
+    verify: bool
 
     # TODO deprecated, unused in the code, should be deleted from db.
     domain: str | None = None
diff --git a/static/js/index.js b/static/js/index.js
index 3e24281..7000bf1 100644
--- a/static/js/index.js
+++ b/static/js/index.js
@@ -96,6 +96,7 @@ window.app = Vue.createApp({
         fixedAmount: true,
         data: {
           disposable: true,
+          verify: false,
           zaps: false
         }
       },
diff --git a/templates/lnurlp/index.html b/templates/lnurlp/index.html
index a0669db..b45461c 100644
--- a/templates/lnurlp/index.html
+++ b/templates/lnurlp/index.html
@@ -249,6 +249,19 @@ <h5 class="text-caption q-mt-sm q-mb-none">
                   />
                 </div>
               </div>
+              <h5 class="text-caption q-mt-sm q-mb-none">
+                LUD-21: verify base spec.
+              </h5>
+              <div class="row">
+                <div class="col-12">
+                  <q-checkbox
+                    dense
+                    :toggle-indeterminate="false"
+                    v-model="formDialog.data.verify"
+                    label="If enabled, a verify URL will be added to LnurlPayActionResponse."
+                  />
+                </div>
+              </div>
               <h5 class="text-caption q-mt-sm q-mb-none">LNURL</h5>
               <div class="row">
                 <div class="col-12">
diff --git a/views_lnurl.py b/views_lnurl.py
index adc88b4..6d990f5 100644
--- a/views_lnurl.py
+++ b/views_lnurl.py
@@ -2,6 +2,7 @@
 from http import HTTPStatus
 
 from fastapi import APIRouter, HTTPException, Query, Request
+from lnbits.core.crud import get_standalone_payment
 from lnbits.core.services import create_invoice
 from lnbits.utils.exchange_rates import get_fiat_rate_satoshis
 from lnurl import (
@@ -12,6 +13,7 @@
     LnurlPayMetadata,
     LnurlPayResponse,
     LnurlPaySuccessActionTag,
+    LnurlPayVerifyResponse,
     Max144Str,
     MessageAction,
     MilliSatoshi,
@@ -120,13 +122,21 @@ async def api_lnurl_callback(
     )
     invoice = parse_obj_as(LightningInvoice, LightningInvoice(payment.bolt11))
 
+    verify: CallbackUrl | None = None
+
+    if link.verify:
+        verify_url = request.url_for(
+            "lnurlp.api_lnurl_verify", payment_hash=payment.payment_hash
+        )
+        verify = parse_obj_as(CallbackUrl, str(verify_url))
+
     if link.success_url:
         url = parse_obj_as(CallbackUrl, str(link.success_url))
         text = link.success_text or f"Link to {link.success_url}"
         desc = parse_obj_as(Max144Str, text)
         action = UrlAction(tag=LnurlPaySuccessActionTag.url, url=url, description=desc)
         return LnurlPayActionResponse(
-            pr=invoice, successAction=action, disposable=link.disposable
+            pr=invoice, successAction=action, disposable=link.disposable, verify=verify
         )
 
     if link.success_text:
@@ -135,9 +145,10 @@ async def api_lnurl_callback(
             pr=invoice,
             successAction=MessageAction(message=message),
             disposable=link.disposable,
+            verify=verify,
         )
 
-    return LnurlPayActionResponse(pr=invoice, disposable=link.disposable)
+    return LnurlPayActionResponse(pr=invoice, disposable=link.disposable, verify=verify)
 
 
 @lnurlp_lnurl_router.get(
@@ -206,3 +217,23 @@ async def lnaddress(
     if not address_data:
         return LnurlErrorResponse(reason="Lightning address not found.")
     return await api_lnurl_response(request, address_data.id)
+
+
+# LUD-21. verify base spec. https://github.com/lnurl/luds/blob/luds/21.md
+@lnurlp_lnurl_router.get(
+    "/api/v1/lnurl/verify/{payment_hash}",
+    name="lnurlp.api_lnurl_verify",
+)
+async def api_lnurl_verify(
+    payment_hash: str,
+) -> LnurlErrorResponse | LnurlPayVerifyResponse:
+    payment = await get_standalone_payment(payment_hash, incoming=True)
+    if not payment:
+        return LnurlErrorResponse(reason="Not found")
+    invoice = parse_obj_as(LightningInvoice, LightningInvoice(payment.bolt11))
+    if payment.success:
+        return LnurlPayVerifyResponse(
+            settled=True, preimage=payment.preimage, pr=invoice
+        )
+    else:
+        return LnurlPayVerifyResponse(settled=False, pr=invoice)