Block confirmations
Also called: confirmations · network confirmations
Definition
Block confirmations are the number of blocks added to a blockchain since the block that includes your transaction, and exchanges wait for a set number before crediting a deposit.
How block confirmations works
When your transaction is included in a block, it has 1 confirmation. Each new block on top adds another. The deeper a transaction sits, the harder it is for the chain to reorganise and drop it, so more confirmations mean more certainty.
Exchanges set their own confirmation requirements for each network, which you can usually see on the deposit page. Requirements also differ by chain: Bitcoin blocks arrive roughly every 10 minutes, while chains like Tron or Solana produce blocks in seconds. Some exchanges credit a deposit for trading after fewer confirmations but unlock withdrawal only after more.
If your deposit shows on an explorer but not on the exchange yet, compare the current confirmation count with the exchange's requirement before contacting support.
Example
Imagine you deposit 0.1 BTC and the exchange requires 2 confirmations to credit and 3 to unlock withdrawal (illustrative numbers). Your transaction enters a block at 14:00. Blocks follow at about 14:09 and 14:21. At 14:09 you have 2 confirmations and the 0.1 BTC appears in your balance. At 14:21 you reach 3 and can withdraw it. Since Bitcoin block times vary, the same deposit could take longer.
Common mistakes
- Contacting support before the deposit has reached the required number of confirmations.
- Expecting every network to confirm as fast as the one you used last time.
- Treating a transaction with 0 confirmations as final.
Learn and practise
FAQ
How many confirmations does Bitcoin need?
There is no single rule. Each exchange sets its own number, and many merchants and individuals treat a few confirmations as sufficient for typical amounts.
Why is my transaction stuck at 0 confirmations?
It is still waiting in the mempool, often because the fee was low compared with other pending transactions.