Bitcoin Address Types Explained
If you've noticed different address formats in your Bitcoin wallets - `1`,`3`, `bc1q` and `bc1p` - you might be wondering what they mean and whether you can safely send funds between them. This guide explains how Bitcoin address prefixes map to different output types, what has changed with each update, and what to check before paying to avoid accidentally sending to the wrong network or an incompatible wallet.
What the prefixes mean
Bitcoin addresses have evolved with the network. The main formats you'll see:
- `bc1`, starting with `bc1q`, use the Bech encoding.
- `bc1`, starting with `bc1p`, are Taproot addresses encoded with Bech32m.
To break down the Bech structure:
- The string has a human-readable part, the separator `1`, and a data part.
- The maximum length is 90 characters.
So, in summary:
- `1` is P2PKH (Pay to Public Key Hash) legacy.
- `3` is P2SH (Pay to Script Hash) legacy, with many potential script types.
- `bc1q` is native SegWit v.
Why the newer formats exist
So what's the difference, and why do these formats matter? The story begins with SegWit.
Then, Taproot activated in November 2021 at block 709,632.
Compatibility and sending safely
The key to securely transferring funds between wallets and networks is matching owners, outcomes and outputs.
Check the following:
Does the recipient software support the sender's address type?
Clear compatibility in both ends is priority one.
How to spy mainnet/testnet mistakes
A second "often mixed up" trap is cross-pollinating Bitcoin and sister networks.
- Note that net look-alikes have different rule-sets and chains
What to check in the wallet
When sending:
- Confirm in both sender and recipient that the wallets are pointing to the right network
- Check the recipient wallet's support docs to confirm it can receive the sender's address type
General information, not financial, investment or tax advice. Rules, fees and allowances change: check the figure with HMRC, the FCA or the service itself before you act.
