Fees & Costs¶
Swaps¶
Swap fees are quoted to you upfront. When you request a quote via POST /swap/quote, the returned amounts already incorporate every cost the swap will pay, so the value you sign is the value that settles. You do not pay anything outside of what the quote shows, and you do not need to hold ETH for gas — it is already included.
You choose how the cost is applied when you ask for the quote:
| Gas Mode | Description |
|---|---|
receive_less | Costs are deducted from your output amount — you spend exactly your input and receive slightly less |
pay_more | Costs are added to your input amount — you receive the full quoted output and spend slightly more |
If you want a line-item view, the quote response includes a fee_breakdown object covering the gas portion of the cost. Order and fill reads use settlement_economics.fees_paid for public, user-visible fees; protocol spread capture and counterparty transfer splits are internal accounting details and are not exposed in public API responses.
Limit Orders¶
Limit orders are settled on-chain when matched. You are responsible for paying gas in real ETH for the settlement transaction. Make sure your wallet has ETH before placing an order — without it, your matched fills cannot settle.
Note
On Sepolia testnet, you can get free test ETH from a faucet.
Withdrawals & Transfers¶
Deposits, withdrawals, and direct ERC-20 transfers built through the API produce a normal Ethereum transaction that you sign and broadcast yourself, so you pay the standard network gas fee for that transaction. There is no separate Sera charge on top of it.