Why a swap sits pending and what to check

You hit "swap". The screen says "pending". Nothing happens for a while. Then either the swap finishes or it does not.

The time between sending your funds and receiving the new ones is not random. It depends on three things: the blockchain you are sending from, the blockchain you are receiving on, and the state of both networks at that moment. Understanding what happens during that wait tells you whether you need to do something or just let it run.

What actually happens between sending and receiving

When you send crypto into a swap, the exchange system watches for your transaction to appear on the source blockchain. That is step one. The system then waits for a number of block confirmations before it considers the deposit final. Only after that does it release the outgoing transaction on the destination chain.

This is why the same swap can take 30 seconds sometimes and 20 minutes other times. A swap between two fast, uncongested chains might confirm in under a minute. The same pair during network congestion can stretch into a quarter of an hour or more. The mechanism is simple: the exchange system does not control how fast blocks are produced or how many confirmations a chain requires.

How many block confirmations do different chains wait for before a swap finishes

Every chain has a different confirmation policy. Bitcoin typically waits for several blocks because reorganisations are possible. Ethereum might wait for twelve or more. A chain like Solana or Polygon waits for fewer because finality comes faster. The exchange sets these numbers conservatively. The goal is to avoid releasing funds on the destination side before the source transaction is irreversible.

You can check the swap status page. It will show how many confirmations have passed and how many are required. If the counter is moving, the swap is progressing. If it has stopped, something else is wrong.

What happens inside a swap when the network suddenly gets congested

Congestion means the mempool fills up. Validators prioritise transactions with higher fees. If your deposit transaction was sent with a low fee, it might sit unconfirmed for a long time. The exchange cannot move until that transaction confirms. This is not a failure of the swap. It is a property of the network you chose.

Some exchanges offer a "speed up" option for the deposit transaction. Others do not. If you sent the deposit yourself and used a low fee, you might need to wait for the mempool to clear or for the transaction to be dropped and replaced. The exchange will not act on an unconfirmed transaction.

Can a swap get stuck for hours and how do you know it is not lost

Yes, a swap can sit for hours. The most common reason is a deposit transaction that refuses to confirm because of low fees or a congested network. Another reason is a destination chain that is itself congested or halted. The exchange will not release funds into a stalled chain.

You know it is not lost because the swap has a status record. The exchange keeps a log of every step. If the deposit transaction is confirmed and the exchange has received it, the funds are safe. They are not going anywhere. The delay is on the exchange's side waiting for confirmations or for the destination chain to become usable.

The danger is the opposite: a transaction that never confirms and eventually drops from the mempool. In that case the funds return to your wallet. The swap never started. You do not lose the money, but you do lose the time.

Why does the estimated time on a swap quote show a window instead of one number

Because no one knows exactly how long a block will take. A window like "5-20 minutes" reflects the range of confirmation times the exchange has observed for that pair under normal conditions. The lower bound is the best case: fast block times, no congestion, quick confirmations. The upper bound accounts for typical variance.

If the window says 5-20 minutes and the swap has been pending for forty, that does not mean the estimate was wrong. It means conditions have changed. The network might be under load. The fee market might have shifted. The estimate is a guide, not a promise.

Can you cancel a crypto swap after the deposit transaction has been sent

No. Once the deposit transaction is broadcast to the network, you cannot recall it. The exchange will see it and begin processing. There is no "cancel" button that reverses a confirmed transaction.

If the deposit is still unconfirmed, you might be able to replace it with a higher-fee transaction using a technique called replace-by-fee (RBF), but that depends on your wallet and the chain. The exchange will see the replacement and use the final confirmed transaction. You cannot tell the exchange to ignore it.

What happens to a swap that does not complete before you close the browser or app

Nothing happens to the swap. It continues running on the exchange's servers. Your browser or app is just a window into that process. Closing it does not stop the exchange from receiving your deposit or sending the outgoing transaction.

When you reopen the site, the swap status should still be available using the transaction ID or the swap ID that was provided when you initiated it. If you did not save that ID, you might lose access to the status page. The swap itself will still complete or fail on its own.

Do weekends and holidays actually slow down crypto swaps or is that a myth

It is partly true and partly myth. Blockchains do not observe weekends. Blocks are produced at the same rate on a Sunday as on a Tuesday. What changes is network congestion. On weekends, retail transaction volume often drops, which can reduce congestion and make swaps faster. On holidays, the opposite can happen if a sudden spike in activity fills the mempool.

The real slowdown is human. Support teams are smaller on weekends. If something goes wrong and you need manual intervention, you might wait longer for a response. The swap mechanism itself does not care what day it is. The people who fix problems do.

What to check while the swap is pending

Look at the swap status page. It will show the deposit transaction hash. Click it or paste it into a block explorer. Check whether the transaction has confirmations. If it has zero after several minutes, the fee might be too low. If it has confirmations but the swap has not moved to the next step, the exchange is waiting for its own internal confirmations.

If the status has not changed for an hour, check the exchange's status page or support channels. Sometimes a specific chain has an issue. Sometimes the exchange is performing maintenance. Most of the time the swap is simply waiting for blocks. Patience is the correct response more often than panic.