Skip to content
blockspace.wiki Start with the basics

timelock

Also: timelocks, nLockTime, OP_CHECKLOCKTIMEVERIFY, CLTV

A rule that holds bitcoin back until a given block height or time. A transaction's nLockTime sets the earliest block or time at which it can be accepted into a block. The OP_CHECKLOCKTIMEVERIFY opcode (BIP 65) does the same for an output: it makes the output unspendable until some point in the future.

Used by: blockspace.loans

Used on #

Sources #

  1. Bitcoin Wiki: NLockTime · en.bitcoin.it/wiki/NLockTime
  2. BIP 65: OP_CHECKLOCKTIMEVERIFY · github.com/bitcoin/bips/blob/master/bip-0065.mediawiki

Updated 2026-10-21 · This page as Markdown

blockspace.wiki is written by Blockspace Co. from its published documents and records and the live data of its own Bitcoin node and indexers. Every page cites its sources; corrections go in the errata.