A reorganisation changes accepted transaction history; inspect the payment again before reacting.
Competing histories
Bitcoin nodes can temporarily learn about different valid blocks extending the same parent. The eventual active chain follows the valid branch with the most accumulated proof of work. When a node switches branches, some previously accepted blocks leave its active history. That switch is a reorganisation. It does not mean every transaction in those blocks was fraudulent, nor does it imply that the network has created duplicate spendable coins.
Trace a hypothetical payment
Suppose branch A includes a payment to a shop, while branch B initially does not. If B becomes the active branch, the shop can see that payment lose its confirmation. The transaction might later appear in another block, remain unconfirmed if still valid, or conflict with a spend accepted on B. These outcomes require different responses. The shop should check the actual output and transaction status rather than assume that disappearance from one block means permanent loss.
Avoid double-counting in records
An accounting integration should retain block hashes and permit provisional entries to be revised. For example, a dashboard that simply adds every observed deposit to a running total can count the same payment twice after reconnection. A better record distinguishes an observed transaction from an accepted deposit and updates its chain association. Preserve an audit trail explaining why a status changed instead of deleting the original observation.
Questions for a service provider
Ask how the service detects reorganisations, whether displayed balances include unconfirmed funds, and when withdrawals become available. Also ask how it corrects a credited deposit whose chain status changes. More confirmations generally increase the work required to replace history, but a fixed count is not a mathematical impossibility boundary. Historical reassurance should not replace a policy designed for the payment's value, delivery method and consequences of reversal.
Sources & context
Sources checked 7 October 2026. This is explanatory coverage, not personalised investment advice. Our corrections policy.
