Spend Permissions

Solana's Token Programs support delegation—granting another account permission to transfer tokens from your token account up to a specified limit. This enables use cases like automated payments, escrow services, and third-party payment processing without giving up custody of your funds.

How Delegation Works

When you approve a delegate, you're authorizing a specific account to transfer tokens on your behalf:

Owner retains custody: You still own the tokens and can transfer or revoke at any time
Capped spending: The delegate can only transfer up to the approved amount
Single delegate per account: Each token account can only have one active delegate
New approval replaces old: Approving a new delegate automatically revokes the previous one

Delegation is non-custodial. The delegate can spend tokens up to the limit, but cannot access or drain the account beyond the approved amount. The owner can revoke at any time.

Business Use Cases

Use Case	How Delegation Helps
Payment processors	Merchant grants processor permission to settle transactions
Automated payroll	Treasury approves payroll service to disburse salaries
Escrow services	Buyer delegates to escrow agent for conditional release
Trading platforms	User approves exchange to execute trades on their behalf
Card issuance	User approves card issuer to charge purchases to their token account

Approving a Delegate

Grant another account permission to spend tokens from your account:

import { getApproveCheckedInstruction } from "@solana-program/token";

// Approve delegate to spend up to 1,000 USDC (6 decimals)
const approveInstruction = getApproveCheckedInstruction({
  source: tokenAccountAddress, // Your token account
  mint: usdcMintAddress, // USDC mint
  delegate: delegateAddress, // Account receiving permission
  owner: ownerKeypair, // You (must sign)
  amount: 1_000_000_000n, // 1,000 USDC in base units
  decimals: 6
});

Parameters:

source: The token account granting permission
delegate: The account that will have spending permission
owner: Current owner of the token account (must sign the transaction)
amount: Maximum tokens the delegate can transfer
decimals: Token decimals for validation (prevents decimal errors)

Revoking a Delegate

Remove all spending permissions from the current delegate:

import { getRevokeInstruction } from "@solana-program/token";

const revokeInstruction = getRevokeInstruction({
  source: tokenAccountAddress, // Your token account
  owner: ownerKeypair // You (must sign)
});

Revoke removes all delegate permissions—there's no partial revoke. If you need to reduce the limit, approve the same delegate with a lower amount.

Checking Delegation Status

Query a token account to see its current delegate and remaining allowance:

import { fetchToken } from "@solana-program/token";

const tokenAccount = await fetchToken(rpc, tokenAccountAddress);

if (tokenAccount.data.delegate) {
  console.log("Delegate:", tokenAccount.data.delegate);
  console.log("Remaining allowance:", tokenAccount.data.delegatedAmount);
} else {
  console.log("No delegate set");
}

Transferring as a Delegate

When acting as the delegate, use a standard transfer but sign with the delegate keypair instead of the owner:

Transfer as Delegate

import { getTransferCheckedInstruction } from "@solana-program/token";

const transferInstruction = getTransferCheckedInstruction({
  source: ownerTokenAccount, // The account you have permission to spend from
  mint: usdcMintAddress,
  destination: recipientTokenAccount,
  authority: delegateKeypair, // You (the delegate) sign, not the owner
  amount: 100_000_000n, // 100 USDC
  decimals: 6
});

The transfer will succeed if:

The source account has sufficient balance
The delegate signs the transaction

Each transfer reduces the remaining allowance. When the allowance reaches zero, the delegate can no longer transfer tokens.

Security Considerations

For account owners:

Only approve trusted delegates
Set the minimum necessary spending limit
Revoke delegations when no longer needed
Monitor your accounts for unexpected transfers

For service providers (delegates):

Clearly communicate the requested spending limit to users
Implement proper key management for your delegate account
Track allowance consumption to request re-approval before limits are exhausted

Delegation vs. Custody

Aspect	Delegation	Full Custody
Token ownership	User retains	User transfers to custodian
Spending control	Capped at approved amount	Full access to transferred funds
Revocation	Instant, by owner	Requires custodian cooperation
Risk exposure	Limited to approved amount	Entire balance
Trust required	Limited	High

Delegation provides a middle ground—enabling automated payments while limiting risk exposure to the approved amount.

Approve Delegate — Technical details on the approve instruction

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