How Does a Transaction’s Confirmation Status Relate to Double-Spending Risk?

The risk of a transaction being reversed (double-spent) decreases significantly with each block confirmation it receives. A zero-confirmation transaction has the highest risk.

Once a transaction is included in a block and that block is followed by subsequent blocks (confirmations), the cost for an attacker to re-mine the chain and reverse the transaction becomes exponentially higher, effectively making the transaction more secure and final.

What Is ‘Probabilistic Finality’ in PoW?
Why Is Transaction Confirmation Important to Prevent Double-Spending?
What Is “Double-Spending” in the Context of a 51% Attack?
How Does Increasing the Confirmation Count Mitigate a Double-Spending Attack?
What Is a “Double-Spend” in the Context of a 51% Attack?
What Is the “Longest Chain Rule” and How Does It Prevent Confirmed Double-Spending?
Why Is a 6-Block Confirmation Depth Considered the Standard for Bitcoin Transactions?
How Does Transaction Finality Relate to the Risk of Double-Spending?

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