> For the complete documentation index, see [llms.txt](https://docs.leather.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.leather.io/learn/what-is-a-bitcoin-segwit-address.md).

# What is a Bitcoin SegWit Address?

A nested SegWit address starts with 3. How it is made, why it exists and how it compares with Native SegWit.

A nested SegWit address starts with `3`, for example `35PBEaofpUeH8VnnNSorM1QZsadrZoQp4N`. It wraps a SegWit output inside a pay-to-script-hash (P2SH) address, so wallets that only knew `1` and `3` addresses could pay to it after the SegWit upgrade of 2017.

Not every `3` address is SegWit: a `3` address can hold any script, such as an older multisig.

## How it is made

* **P2SH-P2WPKH** (single key): the public key is hashed with SHA-256 and RIPEMD-160. That hash forms a small SegWit script. The script is hashed the same way, a version byte (`0x05`) and a checksum are added, and the result is encoded in Base58.
* **P2SH-P2WSH** (scripts such as multisig): the same, but the inner script commits to the SHA-256 hash of a witness script instead of a public key hash.

## Compared with other types

* Cheaper to spend from than a legacy address, because signatures are witness data.
* More expensive than Native SegWit (`bc1q`), because of the extra wrapper script.
* Every wallet can send to it.

See [What is a Native SegWit Address?](/learn/what-is-a-native-segwit-address.md) and [SegWit vs. Native SegWit Addresses](/learn/segwit-native-segwit.md).

## In Leather

Leather sends to nested SegWit addresses. It does not create them: each account uses a Native SegWit and a Taproot address.