<p>Addresses beginning with a 3 generated using <code>addwitnessaddress</code> are called P2SH-P2WPKH addresses. That means it is a Pay-to-Witness-Public-Key-Hash (P2WPKH) script embedded in a Pay-to-Script-Hash (P2SH) address, which starts with a 3. </p>

<p>To restore from that private key, you should be able to just import the key into your wallet and call <code>addwitnessaddress</code> on it again. Note that <code>addwitnessaddress</code> is an experimental RPC call so the method to restoring may change in future, but you can always generate the corresponding public key hash (address) from the key, create a P2WPKH witness script for it, and wrap it in P2SH.</p>

CC BY-SA 3.0
2018-02-10T22:52:32.353Z
2018-02-10T22:52:32.353Z
skang404
<p>The old legacy addresses starts with 1 and the new ones start with 3 and bc1. Can I use my old private key from 2012 to generate a bc1 address? And how so?</p>

CC BY-SA 3.0
2018-02-10T22:59:05.607Z
Why would you want that? You shouldn't reuse a key.
Pieter Wuille
CC BY-SA 3.0
2018-02-14T16:07:41.257Z
I just want to verify if an old btc private key generates a segwit address of bc1 and 3. I just want to understand if its possible or not.
Patoshi パトシ
CC BY-SA 3.0
2018-03-10T07:53:54.970Z
There is no point in that. Use wallet software that supports segwit, and let it generate a new key. Why you'd voluntarily give up your privacy is beyond me.
Pieter Wuille
<address><segregated-witness><address-generation>
Use old legacy bitcoin private key generated from 2012 to generate a segwit address
Patoshi パトシ
# Use old legacy bitcoin private key generated from 2012 to generate a segwit address

(Asked by: username_0 on 2018-02-10)

The old legacy addresses starts with 1 and the new ones start with 3 and bc1. Can I use my old private key from 2012 to generate a bc1 address? And how so?

**Tags:** address, segregated-witness, address-generation

> **Comments:**
> **username_1**: Why would you want that? You shouldn't reuse a key.  
> **username_0**: I just want to verify if an old btc private key generates a segwit address of bc1 and 3. I just want to understand if its possible or not.  
> **username_1**: There is no point in that. Use wallet software that supports segwit, and let it generate a new key. Why you'd voluntarily give up your privacy is beyond me.  

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## 1 answers

### Answer by username_2 on 2018-02-10. Score: 1

Addresses beginning with a 3 generated using `addwitnessaddress` are called P2SH-P2WPKH addresses. That means it is a Pay-to-Witness-Public-Key-Hash (P2WPKH) script embedded in a Pay-to-Script-Hash (P2SH) address, which starts with a 3.

To restore from that private key, you should be able to just import the key into your wallet and call `addwitnessaddress` on it again. Note that `addwitnessaddress` is an experimental RPC call so the method to restoring may change in future, but you can always generate the corresponding public key hash (address) from the key, create a P2WPKH witness script for it, and wrap it in P2SH.


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