How many block confirmations do different chains require before a swap completes

07 September 2026

The number of block confirmations required before a swap completes varies by blockchain, typically ranging from zero to over a hundred. Bitcoin usually requires 6 confirmations, Ethereum needs about 12 to 14, and many proof-of-stake chains settle after 1 to 30 confirmations.

These numbers exist because blockchains are probabilistic systems. A transaction included in a block is not truly final until enough subsequent blocks have been built on top of it. Each additional confirmation reduces the chance that the block containing your transaction will be orphaned or replaced by a competing chain. Different chains make different trade-offs between speed and certainty.

Bitcoin and Bitcoin-like chains

Bitcoin requires 6 confirmations for the exchanger to treat a deposit as settled. This is the standard that has been used since Bitcoin's early years. The reasoning is statistical: after 6 blocks, the probability that an attacker could reorganise the chain and reverse the transaction becomes negligible for practical purposes.

Some Bitcoin-based tokens or sidechains use lower thresholds. Litecoin, for example, often settles after 12 confirmations, but its blocks are generated every 2.5 minutes instead of Bitcoin's 10, so the waiting time is roughly comparable. Dogecoin uses 20 confirmations, which sounds high until you remember its 1-minute block time.

Ethereum and EVM chains

Ethereum's proof-of-stake consensus requires 12 to 14 confirmations for finality. Ethereum actually has a formal concept called "finality" after two epochs, which corresponds to about 12.8 minutes. The exchanger may accept fewer confirmations for smaller amounts, but the full security guarantee takes those 12-14 blocks.

EVM-compatible chains like BNB Smart Chain, Polygon, and Avalanche have their own standards. BSC typically uses 15 confirmations. Polygon uses about 128 confirmations on its Heimdall layer, though the Bor layer confirms faster. These numbers reflect each chain's block time and security model.

Proof-of-stake chains with instant finality

Some chains claim "instant finality" or "single-slot finality". Solana, for instance, treats a transaction as final after 1 confirmation because its consensus mechanism makes reorganisation extremely unlikely under normal conditions. The exchanger may still wait for 2 or 3 confirmations as a safety margin.

Cosmos-based chains using Tendermint consensus achieve finality after one block. Once a block is committed, it cannot be reorganised. The exchanger usually accepts these deposits after 1 to 3 confirmations.

What this means for swap time

The confirmation requirement is only one factor in swap duration. Network congestion, gas prices, and the exchanger's own internal processing all matter. A chain that requires 6 confirmations but has 10-second blocks can settle faster than a chain that requires 1 confirmation but has 30-minute blocks.

The exchanger also adjusts confirmation thresholds based on the swap value. Very large swaps may trigger higher requirements. Very small ones may be accepted sooner. This is why the same chain can sometimes confirm in seconds and other times take over an hour, as covered in the sibling page on variable swap times.

What to do while waiting

Understanding confirmation requirements helps you set realistic expectations. If you are swapping from Bitcoin, expect at least an hour. If you are swapping from Solana, expect seconds. The hub page titled "Why swap times vary and what to do during the wait" explains the full picture, including what you can do while the blocks stack up.

Nothing useful happens by refreshing the swap page. The blocks either come or they do not. Check the chain explorer for your transaction ID. That is the only reliable source of truth. The exchanger's status page will update when the required number of confirmations is reached.

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