> For the complete documentation index, see [llms.txt](https://ms-joe.gitbook.io/a-developers-guide-to-token-extension/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ms-joe.gitbook.io/a-developers-guide-to-token-extension/how-to-make-token-accounts-immutable.md).

# How To Make Token Accounts Immutable

The role of the immutable Owner extension is very easy to understand. What this extension does is, it ensures that ownership of a Token Account cannot be reassigned.

 

For example, if the owner of an existing Associated Token Account is changed, users may unintentionally transfer funds to an account under the assumption that it belongs to the original owner.

With Token Extensions, Associated Token Accounts have the ImmutableOwner extension enabled by default, preventing the ownership from being changed.

The Immutable Owner extension can also be enabled for any new Token Account created by the Token Extension program.

So Devs, this is your guide:

**Step 1: Open this Solana Playground** [**link**](https://beta.solpg.io/656e19acfb53fa325bfd0c46) **with the following starter code:**

 ``// Clientconsole.log("My address:", pg.wallet.publicKey.toString());const balance = await pg.connection.getBalance(pg.wallet.publicKey);console.log(`My balance: ${balance / web3.LAMPORTS_PER_SOL} SOL`);``

 

P.S: *If it is your first time using Solana Playground, you'll first need to create a Playground Wallet and fund the wallet with devnet SOL.*

To get devnet SOL, run the solana airdrop command in the Playground's terminal, or visit this [devnet faucet](https://faucet.solana.com/).

 

**Step 2: Add Dependencies:**

 

\-          Set up your script. For this article, we’ll be using:

  `@solana/web3.js` and `@solana/spl-token` libraries.

\-          Replace the starter code with the following:

`import {  clusterApiUrl,  sendAndConfirmTransaction,  Connection,  Keypair,  SystemProgram,  Transaction,} from "@solana/web3.js";import {  createAssociatedTokenAccount,  createMint,  createInitializeImmutableOwnerInstruction,  createInitializeAccountInstruction,  getAccountLen,  ExtensionType,  TOKEN_2022_PROGRAM_ID,  setAuthority,  AuthorityType,} from "@solana/spl-token"; // Playground walletconst payer = pg.wallet.keypair; // Connection to devnet clusterconst connection = new Connection(clusterApiUrl("devnet"), "confirmed"); // Transaction signature returned from sent transactionlet transactionSignature: string;`

 

**Step 3: Mint Setup.**

 

\-          Create a new mint account before token account.

`// Authority that can mint new tokensconst mintAuthority = pg.wallet.publicKey;// Decimals for Mint Accountconst decimals = 2; // Create Mint Accountconst mint = await createMint(  connection,  payer, // Payer of the transaction and initialization fees  mintAuthority, // Mint Authority  null, // Optional Freeze Authority  decimals, // Decimals of Mint  undefined, // Optional keypair  undefined, // Options for confirming the transaction  TOKEN_2022_PROGRAM_ID, // Token Extension Program ID);`

 

**Step 4: Create Associated Token Account**

`// Create Associated Token Account for Playground walletconst associatedTokenAccount = await createAssociatedTokenAccount(  connection,  payer, // Payer to create Token Account  mint, // Mint Account address  payer.publicKey, // Token Account owner  undefined, // Confirmation options  TOKEN_2022_PROGRAM_ID, // Token Extension Program ID);`

 

\*Attempting to change the owner of the Associated Token Account will result in an error.

`try {  // Attempt to change owner of Associated Token Account  await setAuthority(    connection, // Connection to use    payer, // Payer of the transaction fee    associatedTokenAccount, // Associated Token Account    payer.publicKey, // Owner of the Associated Token Account    AuthorityType.AccountOwner, // Type of Authority    new Keypair().publicKey, // New Account Owner    undefined, // Additional signers    undefined, // Confirmation options    TOKEN_2022_PROGRAM_ID, // Token Extension Program ID  );} catch (error) {  console.log("Expect Error:", error);}`

 

**Step 5: Create Immutable Owner Token Account**

Generate a new keypair for the Token Account and determine the required lamports for rent exemption.

`// Random keypair to use as owner of Token Accountconst tokenAccountKeypair = Keypair.generate();// Address for Token Accountconst tokenAccount = tokenAccountKeypair.publicKey;`

 

Build and send the transaction to create a Token Account with the Immutable Owner extension enabled.

`// Instruction to invoke System Program to create new accountconst createAccountInstruction = SystemProgram.createAccount({  fromPubkey: payer.publicKey, // Account that will transfer lamports to created account  newAccountPubkey: tokenAccount, // Address of the account to create  space: accountLen, // Amount of bytes to allocate to the created account  lamports, // Amount of lamports transferred to created account  programId: TOKEN_2022_PROGRAM_ID, // Program assigned as owner of created account});`

 

`// Instruction to initialize the ImmutableOwner Extensionconst initializeImmutableOwnerInstruction =  createInitializeImmutableOwnerInstruction(    tokenAccount, // Token Account address    TOKEN_2022_PROGRAM_ID, // Token Extension Program ID  );`

 

`// Instruction to initialize Token Account dataconst initializeAccountInstruction = createInitializeAccountInstruction(  tokenAccount, // Token Account Address  mint, // Mint Account  payer.publicKey, // Token Account Owner  TOKEN_2022_PROGRAM_ID, // Token Extension Program ID);`

 

**Step 6: Send Transaction**

``// Add instructions to new transactionconst transaction = new Transaction().add(  createAccountInstruction,  initializeImmutableOwnerInstruction,  initializeAccountInstruction,); // Send transactiontransactionSignature = await sendAndConfirmTransaction(  connection,  transaction,  [payer, tokenAccountKeypair], // Signers); console.log(  "Create Token Account:",  `https://solana.fm/tx/${transactionSignature}?cluster=devnet-solana`,);``

 Run the script by clicking the Run button. Inspect the transaction details on SolanaFM.

Attempting to change the owner of the Token Account will result in the same error as before.

`try {  // Attempt to change owner of Token Account  await setAuthority(    connection, // Connection to use    payer, // Payer of the transaction fee    tokenAccount, // Token Account    payer.publicKey, // Owner of the Token Account    AuthorityType.AccountOwner, // Type of Authority    new Keypair().publicKey, // New Account Owner    undefined, // Additional signers    undefined, // Confirmation options    TOKEN_2022_PROGRAM_ID, // Token Extension Program ID  );} catch (error) {  console.log("Expect Error:", error);}`

And these steps dearest Devs, are your guide to using the Immutable owner extension.