Treasury Teams Should Review Token Approvals Before Bridging

Before a treasury team bridges tokens, it should approve only the contract and amount needed for the deposit. An approval is permission for a contract to spend tokens from a wallet; it does not move the funds by itself. The later deposit transaction moves them through the bridge. Treating those as separate steps helps teams see what each signer is authorising. For a closer look at when funds arrive, see Polygon Bridge. That timing is a separate question from token approval.

What does a token approval allow?

A token approval sets an allowance: the maximum amount a named contract can take from the wallet. Under the common ERC-20 token standard, the wallet owner grants this permission with an approval transaction. The spender can then use a separate transaction to transfer tokens, often as part of a deposit call.

That means a bridge deposit may involve two on-chain steps for a token. First, the treasury wallet approves the bridge’s token-handling contract. Then it submits the deposit. The approval can cost a network fee even if the team later cancels the bridge, and the deposit has its own fee. Native coins and some newer token flows can work differently, so teams should check the specific asset and route.

How should a treasury set the approval amount?

For a one-off transfer, approve the amount the team intends to deposit, plus only any clearly required margin. A limited allowance reduces how much the spender can take if its permissions are misused. A broad or unlimited approval can save a future approval transaction, but it leaves more access in place than a single deposit needs.

Before signing, check the wallet address, source network, token contract, spender address and amount. Confirm the spender against the bridge interface or the organisation’s verified records; a familiar logo is not proof that the contract address is right. Teams can make this review part of the transaction request, so the person who approves the amount also sees the contract that will receive permission.

• Match the token and network to the transfer request.
• Check the spender address against a trusted record.
• Set an allowance that covers the planned deposit.
• Record both the approval and deposit transaction for review.

What should teams do after the deposit?

After the deposit, check whether the allowance remains. Some tokens reduce it as they are spent; if the approval exceeded the deposit, some permission may remain. Teams can review the token’s allowance for that wallet and spender, then set it to zero if no further transfers are planned and the token supports that change. Revoking an allowance is another transaction and may cost a fee.

The practical choice for most treasury teams is to approve the planned amount and review any remainder after the transfer. It takes a little more attention than approving once for unlimited use, but it makes the permission easier to understand and keeps future deposits inside the normal signing process. An approval is not a standing instruction to bridge; it is spending access that deserves its own review.