What happens to a swap already in progress when the network gets congested

07 September 2026

A swap already in progress does not fail due to congestion. It simply waits for confirmation on the sending chain, then waits again for confirmations on the receiving chain. The swap proceeds exactly as designed - only slower.

Why congestion does not break an active swap

The exchanger does not cancel swaps because of network delays. Once you send cryptocurrency to the deposit address, that transaction enters the mempool of the sending blockchain. The swap is now bound to that transaction. The exchanger sees your payment the moment it appears in a block, regardless of how long that block took to be mined.

Think of the swap as a two-stage process. Stage one: you send coins. Stage two: the exchanger sends you the other coins. Congestion can affect either stage, but it cannot undo stage one once it is done.

What actually happens step by step

You initiate a swap. The exchanger gives you a deposit address and a timer. You send your coins. That transaction sits in the mempool, waiting for a miner to include it. During peak congestion on Bitcoin or Ethereum, that wait can stretch from minutes to hours. The exchanger's system checks the blockchain periodically. It sees your transaction only after it is confirmed.

Once confirmed, the exchanger begins the second leg. It takes your deposited coins and sends the agreed-upon amount from its own wallet to your destination address. That transaction also enters the mempool of the receiving chain. If that chain is congested too, the second leg stalls. You see the swap status as "sending" or "awaiting network confirmation" until the receiving chain confirms enough blocks.

The timer and what happens if it expires

Every swap has a time limit. The exchanger sets this limit to protect itself from price volatility. If the sending network is so congested that your transaction does not confirm before the timer runs out, the swap is cancelled. Your coins are returned to you, minus network fees. The exchanger does not keep them.

If your transaction confirms but the receiving chain is congested, the timer does not restart. The exchanger has already received your coins. It is obligated to complete the swap. It will keep retrying the outgoing transaction until it goes through, even if that takes hours. The timer matters only for the deposit phase.

What you should do

If congestion hits while your swap is running, do not send another payment. Do not cancel and retry unless the timer has already expired. Duplicate payments cause confusion and delays. Instead, check the swap status page on the site. It shows whether the exchanger has seen your deposit. If it has, the swap will complete - eventually.

If the timer is still running and your transaction has not confirmed, you have two options. Wait. Or use a higher fee next time. The hub page "Why swap times vary and what to do during the wait" covers fee strategies in detail. That is where you should go for practical advice on avoiding this situation.

A note on different blockchains

Congestion affects chains differently. Bitcoin has a fixed block time of roughly ten minutes, so congestion means waiting for multiple blocks. Ethereum's block time is around twelve seconds, but gas prices spike when the network is busy. A low gas fee on Ethereum can leave your transaction stuck for days. The exchanger cannot override your fee choice. It uses whatever fee you set when sending from your wallet.

Some chains, like Solana or Binance Smart Chain, handle congestion by dropping low-fee transactions entirely. If your deposit gets dropped, the swap fails. You must start over. This is rare but worth knowing.

Summary

Congestion slows swaps. It does not stop them, provided your deposit confirms within the timer. The exchanger handles the rest. Your job is to wait, check the status page, and learn from the experience. The hub page explains how to adjust your fees and timing so that next time, you are not stuck watching a pending transaction for an hour.

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