Different address generated when importing a private key

Question

I used Bitcoin Core 0.19 to create some addresses offline. When I dumped the private keys, I was surprised to see all of them starting with L2… (and the addresses with 3…), but I went for it. I took note of the private keys/addresses.

The next day, I import one of the private keys into another Bitcoin Core wallet, it scans, but the noted address never shows up in my receiving addresses. Instead, it added another address to my list which started with 1B….

So I also added this private key into an Electrum wallet. And surprise, that same address is showing up, not the original one that I got when I created the pair.

What's happening? Is that due to the L2… type?

Answer 1

There are several different types of bitcoin addresses, which can be derived from the same private key. You can see this question for some more info about the different types.

So it sounds like your bitcoin-core wallet is creating P2SH-P2WPKH addresses, but then when you imported it into other wallets, they are deriving a P2PKH address.

So the fix is to instruct the wallet that you are importing the address to, to derive the correct address type. Not every wallet will be able to do this, but some of the more feature-rich options out there should be able to do so.