What it is
When a Bitcoin transaction is broadcast to the network, it enters the mempool. Miners then select transactions to include in new blocks. Once a transaction is included in a block and that block is successfully added to the blockchain, it receives one confirmation. Each subsequent block mined on top of it adds another confirmation, making the transaction progressively more irreversible.
The number of confirmations is a key indicator of a transaction's finality and security. Exchanges and merchants typically require a certain number of confirmations (e.g., 3 or 6 for Bitcoin) before considering a transaction complete and irreversible, especially for large amounts. Higher confirmation counts reduce the risk of a double-spend. News often reports on transaction backlog or confirmation times during periods of network congestion.
Why it matters
Confirmations are crucial for transaction security and finality. They tell you how irreversible a Bitcoin transfer is, impacting when funds become usable.
Reviewed under editorial standardsUpdated September 26, 2026Not investment advice