Bridge Fee Prepayment Tool

WHAT IT DOES

Bridge Fee Prepayment Tool is a developer tool that lets you prepay bridge fees for future cross-chain transactions. Instead of paying fees for each bridge transaction individually, you can deposit a balance of fee tokens into the bridge contract, which is then deducted as you use the bridge. This can save gas costs and streamline the bridging process for frequent users. This tool reads your current prepaid balance, fee parameters, and token balances, then allows you to deposit additional funds, set up auto-top-up rules, and manage your prepayment account. It provides a preview of your current balance, the amount to prepay, auto-top-up settings, and estimated gas cost before you execute, enabling efficient and convenient fee management.

HOW TO USE

Connect your EVM wallet via the BGWallet bridge. Enter the bridge contract address and optionally the fee token address (leave blank for native token). Enter the amount you want to prepay. Choose whether to enable auto-top-up — if enabled, the bridge will automatically top up your prepaid balance when it falls below a threshold you specify. Click "Preview Prepayment" to see your current prepaid balance, the amount to prepay, auto-top-up settings, and estimated gas cost. Review the details carefully. Click "Prepay Fees" to sign and broadcast the transaction. The tool provides a transaction hash for tracking and confirms the prepayment.

TECHNICAL MECHANISM

The tool reads your current prepaid balance from the bridge contract using view functions like `prepaidBalance(address)` or `feeBalance(address)`. It checks the fee token approval if a token is specified, or uses native ETH for native fee payments. When executing, the tool first approves the bridge contract to spend the fee token (if not native), then calls the bridge contract's `prepayFees` or `depositFeeBalance` function with the amount. If auto-top-up is enabled, the tool may also call a function to set the auto-top-up parameters. The entire operation is atomic — if any step fails, the transaction reverts. The tool estimates gas using `estimateGas` and displays the estimated cost before execution.

WHAT IT CANNOT SEE

This tool cannot guarantee that the prepaid fees will be refundable if the bridge contract changes or if the user stops using the bridge before the prepaid amount is fully consumed. Prepaid fees are typically non-refundable or may be subject to a withdrawal process that depends on the bridge contract's implementation. The tool also cannot predict changes to the bridge contract, such as upgrades or modifications to the prepayment interface, that may affect your prepaid balance. Additionally, the tool cannot verify that the bridge will remain operational or that you will use the bridge enough to consume the prepaid amount. Always review the bridge contract's prepayment terms and consider whether prepaying is cost-effective for your usage patterns. This tool is an aid for fee management, not a guarantee that prepaid fees will be refundable.

PLEASE NOTE

EVM chains only. This tool relies on the BGWallet connector and will not function on Solana, Tron, Starknet, SUI, TON, Aptos, Bitcoin, Cosmos, or XRP. The user is responsible for ensuring the supplied bridge contract address is correct and that the contract supports prepayment functions. The fee token must be approved for transfer to the bridge contract. Auto-top-up settings may require additional gas to set up — the tool displays the estimated gas cost before execution.