How many block confirmations does a typical swap wait for on Ethereum compared to Solana

07 September 2026

A typical swap on Ethereum waits for about 12 - 35 block confirmations, while on Solana it waits for just 1 - 2. The difference is not a quirk of the exchanger, but a consequence of how each network finalises transactions.

Ethereum uses probabilistic finality. When a transaction lands in a block, that block is not instantly final. A competing chain could, in theory, replace it. The network’s rule of thumb is that after 12 blocks, the chance of reorganisation becomes negligible. Many services wait longer - some wait 30 or more - because the cost of a reorg, however small, is a lost swap. A typical swap here waits until the Ethereum node reports 12 confirmations, then checks again at 20 and 35. The exact number depends on the swap’s size and the network’s congestion. Larger swaps wait longer. That is not a policy you will see printed anywhere; it is simply what the exchanger’s risk model does.

Solana is different. It uses proof of history and a rotating leader schedule, which gives it a form of optimistic confirmation. A block is voted on by validators almost immediately. After about 400 milliseconds, the network considers a transaction final, and after 1 - 2 slots, most services treat it as done. There is no 12-block wait because there is no meaningful chance of a chain reorganisation after that point. Solana can have forks, but they are resolved in seconds, not minutes. So a typical swap on Solana waits for one or two confirmations, then moves on.

Why does this matter for your swap? Because the confirmation count is not the only thing that decides how long you wait. On Ethereum, the wait for 12 confirmations is roughly 2.5 minutes at a 12-second block time, but if the network is congested, your transaction might sit in the mempool for many minutes before it even gets into a block. On Solana, the confirmation is fast, but the swap might still take time if the network is under load or if the exchanger’s own queue is backed up. The confirmation count is a floor, not a ceiling.

There is a second layer you should know about. The exchanger does not just wait for confirmations on the source chain. It also waits for confirmations on the destination chain before crediting you. If you swap Ethereum for Solana, the process is: wait for Ethereum confirmations, then send the Solana leg, then wait for Solana confirmations. The total time is the sum of both waits, plus any delay in between. A swap that shows “confirmed” on the source chain can still take another minute or two on the destination side.

One practical consequence: on Ethereum, a swap that is stuck at 0 confirmations after ten minutes is not a confirmation problem. It is a mempool problem. The transaction has not been picked up. On Solana, a swap stuck at 0 confirmations after ten seconds is unusual - that suggests a network issue or a dropped transaction. Knowing which chain you are on tells you which failure mode to suspect.

If you are watching a pending swap, the confirmation count is the single most useful number. On Ethereum, watch it climb past 12. On Solana, watch it reach 1 and then stop worrying about that part. What you do while the swap runs, and how to tell a slow confirmation from a genuinely stuck transaction, is the subject of the page this one sits under: “Why your swap is stuck and what to do.” That page covers the common failure modes and what you can actually do about them, which is more useful than staring at a block explorer.

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