diff --git a/examples/main.ts b/examples/main.ts
index b0e95b8..721d22a 100644
--- a/examples/main.ts
+++ b/examples/main.ts
@@ -1,6 +1,6 @@
 import { createWalletClient, http } from "viem";
 
-import { getEmptyBytes, getRandomBytes } from "../src/common/utils/bytes.js";
+import { getRandomBytes } from "../src/common/utils/bytes.js";
 import {
   NetworkType,
   FolksCore,
@@ -23,7 +23,6 @@ async function main() {
   FolksCore.setNetwork(NetworkType.TESTNET);
 
   const accountId: AccountId = getRandomBytes(BYTES32_LENGTH) as AccountId;
-  const refAccountId: AccountId = getEmptyBytes(BYTES32_LENGTH) as AccountId;
 
   // read
   const accountInfo = await FolksAccount.read.accountInfo(accountId);
@@ -46,12 +45,10 @@ async function main() {
 
   const prepareCreateAccountCall = await FolksAccount.prepare.createAccount(
     accountId,
-    refAccountId,
     adapters,
   );
   const createAccountCallRes = await FolksAccount.write.createAccount(
     accountId,
-    refAccountId,
     prepareCreateAccountCall,
   );
 
diff --git a/src/common/constants/lending.ts b/src/common/constants/lending.ts
new file mode 100644
index 0000000..01d7c02
--- /dev/null
+++ b/src/common/constants/lending.ts
@@ -0,0 +1,3 @@
+import { getAccountIdBytes } from "../utils/bytes.js";
+
+export const NULL_ACCOUNT_ID = getAccountIdBytes("");
diff --git a/src/common/utils/bytes.ts b/src/common/utils/bytes.ts
index c14a2e3..5cdce3a 100644
--- a/src/common/utils/bytes.ts
+++ b/src/common/utils/bytes.ts
@@ -2,14 +2,17 @@ import { bytesToHex, pad, toHex } from "viem";
 
 import { BYTES32_LENGTH } from "../constants/bytes.js";
 
+import type { AccountId } from "../types/lending.js";
 import type { Hex } from "viem";
 
 export function getEmptyBytes(length: number): string {
   return pad("0x", { size: length });
 }
 
-export function getAccountIdBytes(accountId: string): Hex {
-  return pad(toHex(Buffer.from(accountId)), { size: BYTES32_LENGTH });
+export function getAccountIdBytes(accountId: string): AccountId {
+  return pad(toHex(Buffer.from(accountId)), {
+    size: BYTES32_LENGTH,
+  }) as AccountId;
 }
 
 export function convertNumberToBytes(
diff --git a/src/xchain/modules/folks-account.ts b/src/xchain/modules/folks-account.ts
index bc5461e..4cd05b2 100644
--- a/src/xchain/modules/folks-account.ts
+++ b/src/xchain/modules/folks-account.ts
@@ -1,6 +1,7 @@
 import { FolksHubAccount } from "../../chains/evm/hub/modules/index.js";
 import { getHubChain } from "../../chains/evm/hub/utils/chain.js";
 import { FolksEvmAccount } from "../../chains/evm/spoke/modules/index.js";
+import { NULL_ACCOUNT_ID } from "../../common/constants/lending.js";
 import { ChainType } from "../../common/types/chain.js";
 import { Action } from "../../common/types/message.js";
 import { assertAdapterSupportsDataMessage } from "../../common/utils/adapter.js";
@@ -42,8 +43,8 @@ import type {
 export const prepare = {
   async createAccount(
     accountId: AccountId,
-    refAccountId: AccountId,
     adapters: MessageAdapters,
+    refAccountId: AccountId = NULL_ACCOUNT_ID,
   ) {
     const folksChain = FolksCore.getSelectedFolksChain();
 
@@ -110,8 +111,8 @@ export const prepare = {
     accountId: AccountId,
     folksChainIdToInvite: FolksChainId,
     addressToInvite: GenericAddress,
-    refAccountId: AccountId,
     adapters: MessageAdapters,
+    refAccountId: AccountId = NULL_ACCOUNT_ID,
   ) {
     const folksChain = FolksCore.getSelectedFolksChain();
 
@@ -313,8 +314,8 @@ export const prepare = {
 export const write = {
   async createAccount(
     accountId: AccountId,
-    refAccountId: AccountId,
     prepareCall: PrepareCreateAccountCall,
+    refAccountId: AccountId = NULL_ACCOUNT_ID,
   ) {
     const folksChain = FolksCore.getSelectedFolksChain();
 
@@ -338,8 +339,8 @@ export const write = {
     accountId: AccountId,
     folksChainIdToInvite: FolksChainId,
     addressToInvite: GenericAddress,
-    refAccountId: AccountId,
     prepareCall: PrepareInviteAddressCall,
+    refAccountId: AccountId = NULL_ACCOUNT_ID,
   ) {
     const folksChain = FolksCore.getSelectedFolksChain();