Can a wallet created before 2021 have a bc1p address?
You found a bc1p address in a wallet you created before November 2021 and you're not sure if that's possible or if something is off.
**A wallet created before November 2021 cannot have shown a bc1p address: that format didn't exist yet.**
bc1p didn't exist before November 2021
bc1p addresses are Taproot addresses. Taproot activated at block 709.632 on 14-nov-2021. Before that block, no wallet could generate or display a bc1p address because the format wasn't defined yet.
The source of this data is BIP-341 + activación de Taproot (bloque 709.632, 14-nov-2021).
What it means if you find a bc1p in an old wallet
If your wallet was created before November 2021 and now shows a bc1p address, the most likely explanation is that the software was updated after that date. Wallets aren't static: a new version can add Taproot support and start showing new addresses.
It's also possible you restored the seed in a newer wallet, or you're looking at an address that wasn't generated by the original version of that wallet. Either way, the address couldn't have been there from the start.
How to check without risking your bitcoin
You don't need to give your seed to anyone to verify this. Look at the wallet's creation date and the first time you saw that bc1p address. If the address is older than November 2021, there's an error or a lie.
If the address appears after November 2021, the explanation is simple: the wallet was updated or you used another tool. It's not a sign you were robbed, but it's also not a guarantee everything is fine on its own.
That the address is from after 2021 doesn't tell you when your wallet was updated
Just because a bc1p address is newer than the Taproot activation doesn't prove your wallet was updated exactly at that moment. An old wallet could have received a software update later and only then started generating bc1p addresses. That doesn't contradict the fact that before November 2021 it couldn't have shown them.
Source: BIP-341 + activación de Taproot (bloque 709.632, 14-nov-2021)