Why does a swap sometimes confirm in seconds and other times take over an hour

07 September 2026

A swap confirms quickly when both the source and destination blockchains are processing few transactions relative to their capacity, and when you have paid a fee that matches current network demand. It takes over an hour when either network is congested, your fee is too low for the prevailing conditions, or the swap involves a blockchain that produces blocks slowly.

What makes a swap fast

The most important factor is network congestion. Every blockchain has a limited number of transactions it can include in each block. When many people are sending transactions at once, miners or validators prioritise those that pay higher fees. If you set a fee that is in line with what other users are paying right now, your swap will typically confirm in the next few blocks.

A second factor is the block time of the blockchain you are using. Bitcoin produces a block roughly every ten minutes. Litecoin produces one every two and a half minutes. Ethereum averages about twelve seconds. If you swap from a slow-blockchain coin, the minimum time to get a confirmation is bound by that blockchain's rhythm. Even in ideal conditions, a Bitcoin swap cannot confirm in seconds - it needs at least one block, which takes minutes.

A third factor is whether the swap involves multiple hops. Some swaps go through an intermediary blockchain or a liquidity provider. Each hop adds a confirmation cycle. A direct swap on a fast chain can settle in seconds. A swap that crosses from a slow chain through an intermediate chain may take many minutes even when everything is working well.

What makes a swap slow

The most common cause of long waits is fee competition. You might have submitted a swap with a fee that was reasonable an hour ago, but then a wave of new transactions arrived and pushed the required fee higher. Your transaction sits in the mempool - the waiting room of unconfirmed transactions - while higher-fee transactions jump ahead. It will eventually confirm, but only when network activity drops back to a level where your fee is competitive again.

Another cause is that the source blockchain itself is temporarily overloaded. Popular NFTs, token launches, or DeFi events can flood a network. During such spikes, even high fees may not guarantee a fast confirmation because the block space is simply too small to fit everyone.

Some blockchains also experience stalls. A validator set might go offline, or a consensus issue might delay block production. These are rare but can stretch a wait from minutes to hours. You cannot predict them, and your swap will only move once the chain resumes normal operation.

The destination blockchain can also cause delays. Your swap might confirm on the source chain quickly, but the counterparty - the exchanger - needs to see enough confirmations on that chain before it releases funds on the destination chain. Some exchanges require six confirmations on Bitcoin, which is about an hour. They do this to protect against reorganisations, where a block is discarded and transactions are reversed. The wait is not your transaction being slow; it is the exchanger waiting for finality.

What you can do while waiting

You can check the status of your swap on the exchanger's site using the swap ID you were given. Most exchangers show whether your transaction is pending on the source chain, confirmed and awaiting destination release, or completed.

You can also check a blockchain explorer for the source chain. Paste your transaction hash into a block explorer. If the transaction is unconfirmed, you will see its fee and its position relative to other pending transactions. If it has been confirmed, you will see the number of confirmations it has received.

If your transaction has been stuck for a very long time - many hours - and the fee was set too low for current conditions, some blockchains allow you to replace it with a higher fee using a mechanism called Replace-by-Fee (RBF). Not all wallets support this, and not all swaps use addresses that let you do it. The exchanger's support page will tell you whether RBF is an option.

If the swap involves a slow blockchain like Bitcoin, and the exchanger requires many confirmations, the wait is structural. There is nothing to do but let it complete. The hub page titled "Why swap times vary and what to do during the wait" explains how to estimate whether a delay is normal or a sign of a problem, and when you should contact support.

A swap that takes over an hour is frustrating but usually not broken. It is most often a matter of fee competition or a blockchain's natural pace. Check the status, be patient, and only intervene if the wait extends far beyond what the blockchain's block time would predict.

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