Segregated Witness: Exchanges, Wallets, Miners, and Companies Planning Integration

Segregated Witness is a proposal by Bitcoin Core developer Pieter Wuille. It uses a new data type to decrease the amount of data stored for each Bitcoin transaction. As a result, more transactions will fit into each block. Wuille’s Segregated Witness (or SegWit) allows for a practical increase in block space without the need for a hardfork.

In addition to scalability improvements, Segregated Witness helps with transaction malleability and decreases the cost to run a full node since less data needs to be stored. For more details, listen to this interview with Eric Lombrozo, or read this explainer.

The following list tracks wallets, exchanges, miners, and other Bitcoin companies that plan to implement Segregated Witness.

Initial Announcement

Eric Lombrozo, a Bitcoin Core dev and contributor to SegWit, announced on the bitcoin-dev mailing list that a number of wallets have already expressed support for SegWit: mSIGNA, GreenAddress, GreenBits, Blocktrail, and NBitcoin.


Nicolas Bacca (btchip), an employee of Bitcoin security company Ledger, announced support for SegWit on reddit:

“We (Ledger) will be working on it soon - the changes to support SegWit are quite limited so I expect every hardware wallet to be compatible with it quickly.”


Aaron Voisine is the CEO and founder of breadwallet, perhaps the most popular Bitcoin wallet for iPhone. In an interview with Bitcoin Magazine, Voisine stated that breadwallet will support SegWit.

Full List

# Name Planned Ready Notes
1 BitcoinJ yes no library
2 Bitcoinjs yes no library
3 BitGo yes no wallet
4 Blocktrail yes no wallet, block explorer
5 BreadWallet yes no wallet
6 Coinfloor yes no exchange
6 Coinkite yes no wallet, hardware wallet
7 Coinomi yes no wallet
8 Digitalbitbox yes no hardware wallet
9 EI8HT yes no wallet
10 Electrum yes no wallet
11 GreenAddress yes no wallet
12 GreenBits yes no wallet
13 Ledger yes no hardware wallet
14 libbtc yes no library
15 libbitcoin yes no library
16 mSIGNA yes yes wallet
17 Mycelium yes no wallet
18 NBitcoin yes no library
19 OmniCore yes no wallet
20 python-bitcoinlib yes no library
21 pycoin yes no library
22 Samourai Wallet yes no wallet
23 Trezor yes no hardware wallet

What is Segregated Witness?

This inforgraph from Holy Transaction breaks down SegWit:

segregated witness

Written by Melvin Draupnir on January 14, 2016.