Bitcoin and chains · 16 / 127 · 2 min

Replace-by-fee

A pending bitcoin transaction can be replaced by a later one that pays a higher fee. Pending is a suggestion.

A worked case

A seller ships on a pending status. The buyer broadcasts a replacement back to themselves. The seller's screen had said sent. The coins moved to the replacement.

Before it is buried

Until miners bury the transaction, the sender can broadcast another that spends the same coins and pays more. Miners prefer the fee.

The shop

A shop that hands over goods because a wallet says pending can watch the payment disappear. The replacement is allowed by the design. The shop trusted a status.

The first broadcast was not the last

Replace-by-fee lets a sender mark a transaction so that a later transaction, spending the same inputs and paying a higher fee, can take its place. Miners take the fee. Until the transaction is buried under more work, the pending line is a bid.

A shop that treats pending as paid is trusting the sender not to bid again. The later bid can pay the sender's own address. The design is public. The loss is the goods.

Read it yourself

• Replace by fee

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