How to Revoke Token Approvals and Why You Must Do It

13 October 2026

A token approval is a smart-contract instruction that lets a DeFi app spend a specific token from your wallet, and if you have ever connected a wallet to a DeFi site, you have almost certainly signed one. You must revoke these approvals because leaving them active means the approved contract can drain those tokens from your wallet at any time, even after you have stopped using the site.

The process of revoking is straightforward: you use a tool or a wallet feature that sends a new transaction setting your allowance for that token and contract to zero. It costs a small network fee, and it is one of the most effective security habits you can adopt in DeFi.

What an approval actually allows

When you first interact with a DeFi protocol, it asks your wallet for permission to spend a token on your behalf. This is the "approve" transaction you see in MetaMask or any other wallet. The permission is not a one-time thing. It persists on the blockchain until you revoke it.

The allowance you grant can be for the exact amount of the trade you are making, or it can be for an unlimited amount. Many sites ask for the maximum possible allowance, often written as uint256.max, so that you do not have to approve again for future trades. That is convenient, but it means the contract can take your entire balance of that token, whenever it wants, and in any amount up to the allowance.

The risk is not theoretical. Smart contracts get exploited. When a contract with an active approval is hacked, the attacker can call the contract and drain tokens from anyone who has approved it. This has happened repeatedly in DeFi history, and the victims are often people who used the protocol once, months earlier, and forgot the approval was still live.

Why you must revoke, not just disconnect

Disconnecting your wallet from a site does nothing to your approvals. Disconnecting only removes the website's access to read your wallet address via the wallet's interface. The approval lives on the blockchain, between your address and the token contract. That relationship remains active until a new transaction changes it.

So the rule is simple: if you have approved a contract, and you are not using it regularly, revoke it. If you are using a protocol you trust, keeping a large allowance may be acceptable, but even then, you should review your allowances periodically. The cost of a revoked approval is a small transaction fee. The cost of forgetting one can be the entire balance of that token.

How to revoke approvals

There are two main ways to revoke: using a dedicated approval-revocation tool, or using a wallet that has a built-in allowance manager. The steps below assume you are using a standard wallet like MetaMask.

Step 1: Use a Revocation Tool (Recommended)

1. Go to a reputable token-approval checker such as Etherscan's "Token Approvals" page, Revoke.cash, or similar services.
2. Connect your wallet. The tool will read your address and list every token approval you currently have active, showing the contract approved, the token, and the allowance amount.
3. Review the list. You will likely see many entries. Some will be from old protocols, some from exchanges, and some you may not recognise at all.
4. Select the approvals you want to revoke. Most tools let you click a "revoke" button next to each entry.
5. Confirm the transaction in your wallet. This will send a new approval transaction with an allowance of zero.
6. Wait for the transaction to confirm. Once confirmed, the allowance is gone.

Step 2: Use Your Wallet's Built-In Tool (If Available)

Some wallets, such as Rabby or certain hardware-wallet interfaces, have a "contracts" or "approvals" section built in. You can find your active approvals there and revoke them directly without visiting a third-party site. The process is the same: select, confirm, wait.

Step 3: Check for Unlimited Approvals

When you are in the revocation tool, look at the allowance amounts. If you see a very large number, or a number with many digits, you are looking at an unlimited approval. These are the most dangerous. Revoke them first. A revoked approval cannot be abused.

How often should you revoke

There is no fixed schedule. A reasonable habit is to check your approvals once a month, and to revoke any that you have not used in that period. If you are actively using a protocol, you may choose to reset the allowance to a smaller amount, or to keep a limited allowance and approve only the exact amount for each trade. The latter is more work, but it shrinks your exposure.

Some people adopt a stricter rule: never leave an approval active for more than one transaction. That is the safest option, but it is not practical for frequent traders. Find a balance that matches how often you use DeFi, and how much you hold in the wallet.

What happens if you do not revoke

The honest answer is that nothing may happen for a long time. Most approvals are never exploited. But the entire point of revoking is that you cannot know which ones will be. A single forgotten approval, on a contract that gets exploited, is enough to lose the funds in your wallet that the approval covers.

The cost of revoking is a network fee, which on many chains is trivial. The cost of not revoking is the potential loss of your entire token balance. In a system where you are your own bank, that is a trade-off you should make in favour of revoking.

A note on phishing

Be careful when using revocation tools. A phishing site that looks like a legitimate approval checker can ask you to connect your wallet, and then ask you to approve a malicious contract. Always double-check the URL, and prefer using a tool you have used before or one recommended by your wallet provider. If a "revocation" site asks you to approve an allowance that is not zero, you are on a scam site. Close it immediately.

The Bottom Line

Token approvals are a necessary part of using DeFi, but they are also a standing invitation to your funds. Revoking them is not complicated, and it is one of the few security actions that costs almost nothing and can save everything. Make it a habit. Your future self, and your wallet balance, will thank you.

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