What a Multi-Hop Cross-Chain Swap Really Costs

A multi-hop cross-chain swap can charge for pool trades and for transactions on both the sending and receiving chains. That matters because the quoted exchange rate is only part of the cost: the amount that arrives can also reflect price impact, network fees and any fee charged by the app routing the trade.

For example, THORChain routes a Bitcoin-to-Ether swap through two liquidity pools: Bitcoin is exchanged for RUNE, then RUNE for Ether. The user sends Bitcoin and receives Ether, without handling RUNE. THORChain’s fee guide describes separate liquidity, inbound, outbound and optional affiliate fees. For more on when this route fits, see this fuller thor swap guide.

What does each hop add to the cost?

Each pool trade can change the price you get, while the source and destination chains charge for their own transactions. A hop is one trade between a pair of assets. In a multi-hop route, the pool balances and fees along every hop help determine the final amount.

THORChain calls its pool charge a liquidity fee. Its docs say this fee depends on “slip”—how much a trade moves the pool’s balance relative to its depth. A larger trade against a shallow pool can have more price impact and a higher liquidity fee. The inbound fee is paid on the source chain when you send funds. The outbound fee comes from the swap output and covers the cost of sending the final asset on its chain. An app may also add an affiliate fee.

How can you compare two routes?

Compare the amount you expect to receive after fees, not just the quoted price or the number of hops. A route with fewer pool trades can still cost more if its pool is shallow or its chain fees are higher. A longer route can be competitive if it uses deeper pools, but each leg adds another price and fee calculation.

• Check the estimated amount received after fees.
• Look at price impact or slippage for each pool leg.
• Account for the source-chain fee and destination-chain fee.
• Check whether the app charges an affiliate or routing fee.

Some protocols split a large trade into smaller trades over time. THORChain calls this a streaming swap. Its documentation says this can reduce price impact without requiring a separate source-chain deposit for each smaller trade, though the swap takes longer to complete. Whether that helps depends on the quote and the time the buyer can wait.

Which route is better for most buyers?

For most buyers, the better route is the one that delivers more of the asset they want for their total spend, with a clear estimate of when it will arrive. Check the final output and fees immediately before sending, because pool conditions and network fees can change. If the quote does not show the fee components or expected output clearly, it is hard to judge the trade’s real cost.