Bitcoin Timelock
Bitcoin can make a spending path unavailable until the network has crossed a chosen time or block height.
Two clocks inside Bitcoin
Absolute timelocks can refer to a block height or time. Relative timelocks measure from the confirmation of a prior output. The exact script and wallet design determine which rule applies.
Recovery and inheritance
A primary key path can coexist with a delayed recovery path. This can support carefully designed inheritance or account recovery arrangements without giving the backup key immediate spending power.
Blocks are not a wall clock
Block intervals vary. A height-based delay is predictable in blocks but only approximate in human time. A time-sensitive plan should include margin for confirmation variance, fee conditions and operational mistakes.
Do not improvise with real funds
Timelocked scripts are unforgiving. Use well-reviewed wallet software, rehearse recovery with test funds, preserve descriptors and backups, and obtain specialist advice for material amounts.