Token approvals: review and revoke

What a token approval (allowance) is, why unlimited approvals are a risk, and how to review and revoke approvals in THORWallet.

Updated 3 min read
Short answer

A token approval lets a smart contract move one of your tokens up to a set amount. Open Settings, tap Token Approvals, and tap Revoke next to any approval you no longer need. Revoking costs a network fee.

On this page

On Ethereum and other EVM networks, a contract cannot touch your tokens until you approve it. The approval stays active after the swap or deposit is done, until it is used up or you revoke it. THORWallet lists your open approvals in one place.

How approvals work

  • An approval names one token, one spender (the contract that may move it) and an amount.
  • Unlimited means the spender may move any amount of that token, now and later.
  • An approval is not a payment. It is a permission. It only becomes a loss if the spender misuses it.
  • Coins such as ETH or BTC themselves need no approval. Approvals exist for tokens on EVM networks.

When a swap in THORWallet needs an approval, the app shows the Approve contract screen first, with the amount, the token's Contract Address, the Authorized Address and the fee. Tap the edit icon to Set custom approval amount if you want to approve less. For some routes THORWallet asks for a One-time approval instead, after which later swaps of that token need only a signature.

Review your approvals

  1. On the wallet home screen, tap the gear icon to open Settings.
  2. Under Web 3, tap Token Approvals.
  3. The list is grouped by network. Each row shows the token, the spender, the Approved amount and, where known, the value At risk in USD.

Pull down to refresh the list. It shows the approvals of the wallet that is selected in the app.

Revoke an approval

  1. In Token Approvals, tap Revoke next to the approval.
  2. Check the Review Details sheet: token, spender, Approved amount, network, Contract Address, Authorized Address and the fee.
  3. Tap Revoke and confirm when the app asks.
  4. The row shows Revoking... until the network confirms the transaction. Then it disappears.
Tip

Revoke approvals marked Unlimited for apps you no longer use first. These carry the most risk.

If something goes wrong

The Revoke button is greyed out

You need the network's own coin for the fee. THORWallet shows Not enough with the coin name, for example ETH on Ethereum or Arbitrum. Add a small amount and try again.

"Failed to load fees"

The fee could not be fetched. Wait a moment, close the sheet and open it again.

The approval is still listed after I revoked it

The transaction may not be confirmed yet. Pull down to refresh after a minute. Check Activity if it does not change.

I approved something on a scam site

Revoke it now, then read Stay safe from scams. A revoke stops future use of the approval. It does not bring back tokens that were already moved.

The approval list is in the mobile app. Support will never ask for your recovery phrase.

Common questions

What is a token approval?

It is a permission you sign on an EVM network that lets one contract, the spender, move one of your tokens up to an approved amount. Swaps and lending protocols need it before they can use a token.

Is an unlimited approval dangerous?

It can be. The spender can move all of that token from your wallet at any time. If the contract is malicious or gets hacked, the tokens are at risk until you revoke the approval.

Does revoking cost money?

Yes. A revoke is a transaction on the network, so you pay a network fee in that network's coin, for example ETH on Ethereum.

Why is the approval list empty?

The selected wallet has no open approvals on the networks THORWallet checks, and the screen shows No active token approvals. Pull down to refresh if you expected one.

Do I have to approve again after I revoke?

Yes. The next time you use that token with the same contract, THORWallet asks you to approve it again.

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