Most cryptocurrency exchanges require between 1 and 3 confirmations for Bitcoin transactions. When we’re talking about “confirmations” in the context of Bitcoin, we’re referring to the number of blocks that have been added to the Bitcoin blockchain since a transaction was completed.
The more confirmations a transaction has, the more certain we can be that a transaction will not be reversed and that it will be permanently recorded on the Bitcoin blockchain.
How many confirmations are required for Bitcoin?
The amount of confirmations that are required before a Bitcoin transaction is considered final depends on the business or person that you are sending Bitcoin to.
For example, each cryptocurrency exchange has a set number of Bitcoin confirmations that they require before they credit your BTC deposit to your Bitcoin account or finalize your withdrawal.
The amount of Bitcoin confirmations required by an exchange can sometimes vary according to the size of the transactions — for example, an exchange might only require 2 confirmations for smaller transactions, while 6 confirmations might be necessary for large transactions.
In the past, 6 confirmations used to be somewhat of an industry standard for Bitcoin transactions. Now, exchanges will usually require fewer confirmations before they consider your Bitcoin deposit as final and credit your account. Today, the industry standard is between 1 and 3 confirmations.
Here’s how many confirmations for Bitcoin are required by some of the biggest cryptocurrency exchanges:
Exchange Confirmations Binance 1 for deposits, 2 for withdrawals Coinbase 2 Kraken 3 Crypto.com 2 Bitstamp 3 OKX 1 for deposits, 3 for withdrawals Bitget 1 Bitfinex 3
Bitcoin confirmations explained
The number of confirmations a Bitcoin transaction has simply means the number of blocks that have been added to the Bitcoin blockchain since the transaction was added to the blockchain.
Visualization of new blocks being added to the Bitcoin blockchain.
For example, let’s say you made a Bitcoin transaction that first got included in block 820,000. Here’s how the number of confirmations would grow as new blocks are added to the Bitcoin blockchain.
Block height Confirmations 820,000 1 820,001 2 820,002 3 820,003 4 820,004 5 820,005 6
The reason why the number of confirmations is important is because the business or person accepting Bitcoin wants to protect themselves from a double-spend attack, in which someone spends the same BTC more than once.
While the probability of someone being able to double-spend Bitcoin is very low, it’s not impossible. Double-spending BTC coins becomes increasingly difficult as additional blocks are added to the Bitcoin blockchain. This is why many exchanges and merchants that accept Bitcoin will require a transaction to have more than 1 confirmation before it is considered final.
The Proof-of-Work algorithm used by Bitcoin is designed to target a 10 minute block time. This means that a new block is added to the Bitcoin blockchain approximately every 10 minutes. The block time fluctuates around this 10 minute target due to the constantly changing amount of hashrate on the Bitcoin network, periodic Bitcoin mining difficulty adjustments and random chance.
So, each confirmation takes roughly 10 minutes. If you’re depositing Bitcoin to an exchange that requires 3 confirmations for BTC deposits, you can therefore expect your deposit to be credited to your account in about 30 minutes.
How to check the amount of Bitcoin confirmations?
Many Bitcoin wallets will allow you to check the number of confirmations a transaction you sent currently has.
Alternatively, you can use a Bitcoin block explorer to check how many new blocks have been added to the Bitcoin blockchain since your transaction was included in a block. Block explorers are free tools that display a wealth of information about Bitcoin blocks and transactions included in them. Here are some of the most popular Bitcoin block explorers:
- Blockchain.com Explorer
- Blockstream.info
- BlockCypher
- Blockchair
Block explorers provide extremely detailed information about what’s happening on the Bitcoin blockchain.
The bottom line — Waiting for Bitcoin confirmations is tedious, but necessary to ensure security
Every active crypto trader knows the feeling — you’re itching to make a crypto trade but are stuck waiting for your Bitcoin deposit to reach the required number of confirmations. While this is annoying, exchanges and other businesses accepting crypto need to wait for additional confirmations to protect themselves against the possibility of a double-spend attack.
If you want to learn more about how Bitcoin transactions are processed and how the Bitcoin protocol is structured, make sure to have a look at our article discussing the Bitcoin halving.
