diff --git a/modules/abstract-lightning/src/codecs/api/withdraw.ts b/modules/abstract-lightning/src/codecs/api/withdraw.ts
index c0494dfba3..74800c1b37 100644
--- a/modules/abstract-lightning/src/codecs/api/withdraw.ts
+++ b/modules/abstract-lightning/src/codecs/api/withdraw.ts
@@ -1,20 +1,22 @@
 import * as t from 'io-ts';
-import { LightningOnchainRecipient } from '@bitgo/public-types';
+import { LightningOnchainRequest, optionalString } from '@bitgo/public-types';
 import { PendingApprovalData, TxRequestState } from '@bitgo/sdk-core';
-import { BigIntFromString } from 'io-ts-types';
 
 export const WithdrawStatusDelivered = 'delivered';
 export const WithdrawStatusFailed = 'failed';
 
 export const WithdrawStatus = t.union([t.literal(WithdrawStatusDelivered), t.literal(WithdrawStatusFailed)]);
 
-export const LightningOnchainWithdrawParams = t.type({
-  recipients: t.array(LightningOnchainRecipient),
-  satsPerVbyte: BigIntFromString,
-  // todo:(current) add passphrase
-  // passphrase: t.string,
-});
-
+export const LightningOnchainWithdrawParams = t.intersection([
+  LightningOnchainRequest,
+  t.type({
+    passphrase: t.string,
+  }),
+  t.partial({
+    sequenceId: optionalString,
+    comment: optionalString,
+  }),
+]);
 export type LightningOnchainWithdrawParams = t.TypeOf<typeof LightningOnchainWithdrawParams>;
 
 export const LndCreateWithdrawResponse = t.intersection(
diff --git a/modules/abstract-lightning/src/wallet/lightning.ts b/modules/abstract-lightning/src/wallet/lightning.ts
index 3801d4a9a2..7f2c0be975 100644
--- a/modules/abstract-lightning/src/wallet/lightning.ts
+++ b/modules/abstract-lightning/src/wallet/lightning.ts
@@ -29,7 +29,7 @@ import {
   ListPaymentsResponse,
   LndCreateWithdrawResponse,
 } from '../codecs';
-import { LightningPaymentIntent, LightningPaymentRequest } from '@bitgo/public-types';
+import { LightningPaymentIntent, LightningPaymentRequest, LightningOnchainRequest } from '@bitgo/public-types';
 
 export type PayInvoiceResponse = {
   /**
@@ -167,6 +167,9 @@ export interface ILightningWallet {
    * @param {LightningOnchainWithdrawParams} params - Withdraw parameters
    * @param {LightningOnchainRecipient[]} params.recipients - The recipients to pay
    * @param {bigint} params.satsPerVbyte - Value for sats per virtual byte
+   * @param {string} params.passphrase - The wallet passphrase
+   * @param {string} [params.sequenceId] - Optional sequence ID for the respective withdraw transfer
+   * @param {string} [params.comment] - Optional comment for the respective withdraw transfer
    * @returns {Promise<LightningOnchainWithdrawResponse>} Withdraw result containing transaction request details and status
    */
   withdrawOnchain(params: LightningOnchainWithdrawParams): Promise<LightningOnchainWithdrawResponse>;
@@ -336,12 +339,25 @@ export class LightningWallet implements ILightningWallet {
     const reqId = new RequestTracer();
     this.wallet.bitgo.setRequestTracer(reqId);
 
+    const { userAuthKey } = await getLightningAuthKeychains(this.wallet);
+    const userAuthKeyEncryptedPrv = userAuthKey.encryptedPrv;
+    if (!userAuthKeyEncryptedPrv) {
+      throw new Error(`user auth key is missing encrypted private key`);
+    }
+    const signature = createMessageSignature(
+      t.exact(LightningOnchainRequest).encode(params),
+      this.wallet.bitgo.decrypt({ password: params.passphrase, input: userAuthKeyEncryptedPrv })
+    );
+
     const paymentIntent: { intent: LightningPaymentIntent } = {
       intent: {
-        onchainRequest: {
+        comment: params.comment,
+        sequenceId: params.sequenceId,
+        signedRequest: {
           recipients: params.recipients,
           satsPerVbyte: params.satsPerVbyte,
         },
+        signature,
         intentType: 'payment',
       },
     };
diff --git a/modules/bitgo/test/v2/unit/lightning/lightningWallets.ts b/modules/bitgo/test/v2/unit/lightning/lightningWallets.ts
index 784823e29b..cb3b0f4283 100644
--- a/modules/bitgo/test/v2/unit/lightning/lightningWallets.ts
+++ b/modules/bitgo/test/v2/unit/lightning/lightningWallets.ts
@@ -825,6 +825,7 @@ describe('Lightning wallets', function () {
           },
         ],
         satsPerVbyte: 15n,
+        passphrase: 'password123',
       };
 
       const txRequestResponse = {
@@ -973,6 +974,7 @@ describe('Lightning wallets', function () {
           },
         ],
         satsPerVbyte: 15n,
+        passphrase: 'password123',
       };
 
       const txRequestResponse = {
diff --git a/modules/express/test/unit/lightning/lightningWithdrawRoutes.test.ts b/modules/express/test/unit/lightning/lightningWithdrawRoutes.test.ts
index 29a69cfef7..a941dcca8a 100644
--- a/modules/express/test/unit/lightning/lightningWithdrawRoutes.test.ts
+++ b/modules/express/test/unit/lightning/lightningWithdrawRoutes.test.ts
@@ -32,6 +32,7 @@ describe('Lightning Withdraw Routes', () => {
           },
         ],
         satsPerVbyte: '15',
+        passphrase: 'password123',
       };
 
       const expectedResponse: LightningOnchainWithdrawResponse = {
@@ -84,6 +85,7 @@ describe('Lightning Withdraw Routes', () => {
       // we decode the amountMsat string to bigint, it should be in bigint format when passed to payInvoice
       should(firstArg).have.property('recipients', decodedRecipients);
       should(firstArg).have.property('satsPerVbyte', BigInt(inputParams.satsPerVbyte));
+      should(firstArg).have.property('passphrase', BigInt(inputParams.satsPerVbyte));
     });
 
     it('should throw an error if the satsPerVbyte is missing in the request params', async () => {
@@ -94,6 +96,7 @@ describe('Lightning Withdraw Routes', () => {
             address: 'bcrt1qjq48cqk2u80hewdcndf539m8nnnvt845nl68x7',
           },
         ],
+        passphrase: 'password123',
       };
 
       const req = mockRequestObject({
@@ -110,6 +113,29 @@ describe('Lightning Withdraw Routes', () => {
     it('should throw an error if the recipients is missing in the request params', async () => {
       const inputParams = {
         satsPerVbyte: '15',
+        passphrase: 'password123',
+      };
+
+      const req = mockRequestObject({
+        params: { id: 'testWalletId', coin },
+        body: inputParams,
+      });
+      req.bitgo = bitgo;
+
+      await should(handleLightningWithdraw(req)).be.rejectedWith(
+        'Invalid request body for withdrawing on chain lightning balance'
+      );
+    });
+
+    it('should throw an error if passphrase is missing in the request params', async () => {
+      const inputParams = {
+        satsPerVbyte: '15',
+        recipients: [
+          {
+            amountSat: '500000',
+            address: 'bcrt1qjq48cqk2u80hewdcndf539m8nnnvt845nl68x7',
+          },
+        ],
       };
 
       const req = mockRequestObject({