<p>Like a cheque with a date in future, a Bitcoin transaction with locktime cannot be unlocked (read cashed) before that date. The definition in bitcoin.org is pretty clear</p>

<blockquote>
  <p>Part of a transaction which indicates the earliest time or earliest
  block when that transaction may be added to the block chain.</p>
</blockquote>

<p>Sample use case is a cautionary deposit. For a great example see micropayment channel protocol implemented by bitcoinj and described here: </p>

<p><a href="https://bitcoinj.github.io/working-with-micropayments" rel="nofollow">https://bitcoinj.github.io/working-with-micropayments</a></p>

CC BY-SA 3.0
2016-02-25T22:50:07.050Z
You lost me there with all the A B Q Tx Tx2 variables.
Patoshi パトシ
CC BY-SA 3.0
2016-02-25T22:56:46.910Z
well, reedited with Alice and Bob. Not easy to explain without the proper actors
Davide C
CC BY-SA 3.0
2016-02-25T23:16:55.100Z
what is coin Q?
Patoshi パトシ
CC BY-SA 3.0
2016-02-25T23:25:50.380Z
a coin is a sum linked to the output of a past transaction and that can be spent becoming the input of another.
Davide C
CC BY-SA 3.0
2016-02-25T22:47:28.397Z
2016-02-28T14:35:31.497Z
2016-02-28T14:35:31.497Z
Davide C
<p>What is Bitcoin's locktime feature and what are some example use cases? </p>

<p>And how can a user make use of this new feature? Is it in any gui wallet? And how would one use it in the command line if its the only option?</p>

CC BY-SA 4.0
2024-02-29T19:30:38.447Z
Does https://bitcoin.stackexchange.com/q/23792/5406 answer your question?
Murch
<locktime>
What is Bitcoin's locktime feature exactly? How can it be used?
Patoshi パトシ
# What is Bitcoin's locktime feature exactly? How can it be used?

(Asked by: username_0 on 2016-02-25)

What is Bitcoin's locktime feature and what are some example use cases?

And how can a user make use of this new feature? Is it in any gui wallet? And how would one use it in the command line if its the only option?

**Tags:** locktime

> **Comments:**
> **username_1**: Does https://bitcoin.stackexchange.com/q/23792/5406 answer your question?  

---

## 1 answers

### Answer by username_2 on 2016-02-25. Score: 3 | Accepted answer

Like a cheque with a date in future, a Bitcoin transaction with locktime cannot be unlocked (read cashed) before that date. The definition in bitcoin.org is pretty clear

> Part of a transaction which indicates the earliest time or earliest
> block when that transaction may be added to the block chain.

Sample use case is a cautionary deposit. For a great example see micropayment channel protocol implemented by bitcoinj and described here:

<https://bitcoinj.github.io/working-with-micropayments>

> **Comments:**
> **username_0**: You lost me there with all the A B Q Tx Tx2 variables.  
> **username_2**: well, reedited with Alice and Bob. Not easy to explain without the proper actors  
> **username_0**: what is coin Q?  
> **username_2**: a coin is a sum linked to the output of a past transaction and that can be spent becoming the input of another.  

---

