Approvals are spending permissions
Distinguish connecting a wallet, sending tokens and authorizing future spending.
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A token approval grants a spender permission to move a token under defined rules. It is not necessarily a transfer now. On common ERC-20 tokens, the allowance belongs to a combination of owner, token and spender on one network.
Four actions that look similar
| Action | Immediate effect | Continuing authority? |
|---|---|---|
| Connect a wallet | Exposes selected account information to an app | Normally no token spending permission |
| Transfer | Sends assets now | No authority beyond the transfer |
| Approval | Lets a spender transfer up to an allowance | Yes, until exhausted, changed or revoked |
| Signed permit | Authorizes an allowance through a signature | It may be submitted later by someone else |
Some token systems also support operator approvals for whole NFT collections. Solana token delegates have different mechanics. Do not assume an ERC-20 revoke interface covers all networks or permissions.
Limit the exposure
If a swap needs 25 units, compare an allowance for 25 with an unlimited allowance. A narrower permission reduces the amount exposed to that spender, but may require another approval next time. It does not protect funds already deposited in a protocol.
Disconnecting a site does not remove onchain allowances. Revoking a permission changes it onchain and may require a fee. It cannot recover funds already moved or fix a compromised signing key.
Before signing a permit, inspect the token, spender, amount, network and expiry where present. A signature without a gas fee can still authorize spending. Never treat “sign message” as automatically harmless.
tip — To remove an allowance, follow Revoke an unnecessary token approval. Disconnecting the site is not a substitute.