Liquality does not charge fees for transactions or swaps. However, the market rate for a pair is determined by set market makers, who usually charge a 1% spread. Additionally, users will need to pay mining fees, which are charged by the network. Keep in mind that each atomic swap will require at least two transactions (one to initiate your swap, another to claim your new funds) on your end. Swapping an ERC20 will require three (an additional transaction to approve the ERC20 transfer).
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