diff --git a/mintlify/platform-overview/core-concepts/quote-system.mdx b/mintlify/platform-overview/core-concepts/quote-system.mdx
index f6997418c..301405221 100644
--- a/mintlify/platform-overview/core-concepts/quote-system.mdx
+++ b/mintlify/platform-overview/core-concepts/quote-system.mdx
@@ -226,6 +226,41 @@ curl -X POST https://api.lightspark.com/grid/2025-10-13/quotes/Quote:abc123/exec
 }
 ```
 
+### Strong Customer Authentication (EU Customers)
+
+For customers in regions where Strong Customer Authentication (SCA) is required (e.g., EU), quotes may enter a `PENDING_AUTHORIZATION` status with an `scaChallenge` object. The customer must authorize the challenge before the quote can be executed.
+
+**Quote response with SCA challenge:**
+
+```json
+{
+  "id": "Quote:019542f5-b3e7-1d02-0000-000000000050",
+  "status": "PENDING_AUTHORIZATION",
+  "scaChallenge": {
+    "id": "ScaChallenge:...",
+    "expiresAt": "2025-10-03T12:05:00Z",
+    "factor": "SMS_OTP",
+    "availableFactors": ["SMS_OTP", "PASSKEY"],
+    "purpose": "PAYOUT"
+  }
+}
+```
+
+To authorize the quote, call `POST /quotes/{quoteId}/authorize` with the appropriate proof:
+
+```bash
+curl -X POST https://api.lightspark.com/grid/2025-10-13/quotes/Quote:abc123/authorize \
+  -u "$GRID_CLIENT_ID:$GRID_CLIENT_SECRET" \
+  -H "Content-Type: application/json" \
+  -d '{"code": "123456"}'
+```
+
+<Note>
+  Multiple authorizations may be required in sequence (e.g., currency conversion + payout). After each authorization, check the quote status — if still `PENDING_AUTHORIZATION`, authorize the next challenge.
+</Note>
+
+For JIT-funded quotes, `paymentInstructions` are withheld until all SCA challenges are satisfied.
+
 ### Execution Timing
 
 <Tabs>
diff --git a/mintlify/platform-overview/core-concepts/transaction-lifecycle.mdx b/mintlify/platform-overview/core-concepts/transaction-lifecycle.mdx
index c9ed40fa3..d73486dd1 100644
--- a/mintlify/platform-overview/core-concepts/transaction-lifecycle.mdx
+++ b/mintlify/platform-overview/core-concepts/transaction-lifecycle.mdx
@@ -121,6 +121,7 @@ A single `status` field represents whether the transaction reached its destinati
 | Status | Description |
 |--------|-------------|
 | **PENDING** | Quote is pending confirmation |
+| **PENDING_AUTHORIZATION** | Awaiting Strong Customer Authentication. Only occurs for customers in regions where SCA is required (e.g., EU); authorize the transaction's `scaChallenge` to proceed. |
 | **EXPIRED** | Quote wasn't executed before the expiry window |
 | **PROCESSING** | Executing the quote after receiving funds (checking internal balances, or push/pull to/from external account) |
 | **COMPLETED** | Payout successfully reached the destination account |
@@ -135,6 +136,9 @@ A single `status` field represents whether the transaction reached its destinati
 ```mermaid
 stateDiagram-v2
     [*] --> PENDING : Quote created
+    PENDING --> PENDING_AUTHORIZATION : SCA required (EU)
+    PENDING_AUTHORIZATION --> PROCESSING : Authorized
+    PENDING_AUTHORIZATION --> EXPIRED : Challenge expired
     PENDING --> PROCESSING : Quote confirmed, funds received
     PENDING --> EXPIRED : Quote expired before execution
     PROCESSING --> COMPLETED : Payout reached destination
@@ -190,6 +194,7 @@ Outgoing payment webhooks use the format `OUTGOING_PAYMENT.<STATUS>`. The webhoo
 | Event | Description |
 |-------|-------------|
 | `OUTGOING_PAYMENT.PENDING` | Transaction created, quote pending confirmation |
+| `OUTGOING_PAYMENT.PENDING_AUTHORIZATION` | Awaiting Strong Customer Authentication (EU customers only) |
 | `OUTGOING_PAYMENT.PROCESSING` | Quote confirmed, payout in progress |
 | `OUTGOING_PAYMENT.COMPLETED` | Payout reached destination |
 | `OUTGOING_PAYMENT.FAILED` | Payout failed |
@@ -270,6 +275,11 @@ app.post('/webhooks/grid', async (req, res) => {
   const { data, type } = req.body;
 
   switch (type) {
+    case 'OUTGOING_PAYMENT.PENDING_AUTHORIZATION':
+      // EU customers only: prompt user to complete SCA challenge
+      await notifyCustomer(data.customerId, 'Authorization required to complete payment.');
+      break;
+
     case 'OUTGOING_PAYMENT.COMPLETED':
       await notifyCustomer(data.customerId, 'Payment delivered!');
       break;