Topic: Set Up Multi Signature Wallet (Read 154 times)

1. Please do testing, so you know how it works.
2. You can do it all from one computer, for testing purposes (not for real production live with large amount of bitcoins, ... you can, but that's not wise.)
3. You can create, for example, 3 wallets with the master public keys and then use those to make a 2-of-3 multi-sig watch-wallet, create a transaction, export that, then either on that same computer or another one use the private key or seed to make wallets that can sign the transaction.
4. Current version of Electrum can create multi-sig wallet of up to 15.. I tried it (I don't have 15 different computers, I just made them all in the same computer.)
5. You can probably use the make_seed console command on an offline computer to generate seeds in bulk safely.
6. There are tutorials out there for hardware wallets, but I don't have any experience with them personally as I've never had one. Still don't. I have lots of old hardware which I use offline as my own personal hardware wallet. Yes, they are big and bulky, and even the cheapest tablet is still 7 or 8 inches. The closest I'm considering would be from any of the top brands: Coldcard, Trezor, and Ledger. I feel that I'll end up still using a laptop anyway. There's a guide out there for using Raspberry Pis as cold storage if you're inclined, but you end up having to buy all the required stuff: keyboard, mouse, monitor, camera.
7. Having used Electrum on both desktop and android platforms, I like and prefer using QR codes to shuffle transaction data between the watch-only wallet and the offline wallets. I use a third device to broadcast the final signed transaction.
8. Can't wait for Taproot for Electrum wallets. This is going to be a game changer.

You can use same Electrum wallet but you must send coins to new generated multisig address.
Few months ago I made a list of all wallets that support multisig:

• Electrum wallet
• Armory wallet
• Green wallet
• Lily wallet
• Specter wallet
• Sparrow wallet
• Nunchuk wallet
• Blue wallet
• Caravan wallet
• ColdCard hardware wallet
• Keystone hardware wallet
• BitBox hardware wallet
• SeedSigner DIY Wallet
• Trezor Hardware wallet*
• Ledger Hardware wallet*

* Can't construct multisig or it can't be verified

It is more secure if you do it properly, but it also add another level of complexity and that is something you should be aware of.
If you have small amount of BTC maybe worth few hundred of dollars it doesn't make any sense to have multisigm, but if you have a fortune then you need more security and complexity.
Before doing real multisig you can play around with testnet to see how it works and maybe listen some videos from Andreas Antonopoulos about multisig.

Sure, but they are still derived from the same seed phrase, and so the same seed phrases can still be used to create a multi-sig wallet. Just as Electrum won't let you use an xpub to generate a segwit wallet, it won't let you use a zpub to generate a multi-sig wallet, but the same seed phrase can quite happily generate an xpub, ypub, zpub, Ypub, and Zpub.

There is nothing inherently different between the seed phrases Electrum generates if you choose a standard wallet or a multi-sig wallet. Both options generate segwit versioned seed phrases. You can try this yourself by telling Electrum to generate you a multi-sig wallet, and then import one of the seed phrases as a standard wallet, and create a bunch of addresses as normal. The thing that differs between the two wallets is how it uses that seed phrase, not the seed phrase itself.

I experimented it immediately went I saw the OP question before posting.

I used two old Electrum standard wallet seed phrases and both generated Zpub keys while importing it on multisig, that is entirely different from zpub keys that they both are on standard wallets. And this can be used to set up the multisig wallet that its keys will be surely different, but which I advice better to generate new seed phrase instead.

I used the zpub keys from the standard wallet but it displayed this error 'Wrong key type p2wpkh'.

All I was referring to are zpub key and Zpub key.

I was not confused about the master public keys in relation to what HCP posted, although I did not know one started from upper case and the other as lower case, but I did understand what happened and that the zpub dispalyed error while importing it as multisig type. Thanks for pointing that out.

I think maybe he is confused due to the different types of public key between different types of Electrum wallet.

If you create a standard single-sig Electrum wallet, your public key will be a zpub.
If you wish to create a standard multi-sig Electrum wallet, then you need to use public keys of the Zpub variety.
If you try to create a multi-sig electrum wallet using zpubs instead of Zpubs, you will be shown the error "Wrong key type p2wpkh".
You can see the differences on github here: https://github.com/spesmilo/electrum-docs/blob/master/xpub_version_bytes.rst#specification

But there is nothing stopping you from using a pre-existing single-sig seed phrase to derive the Zpub necessary to set up a multi-sig wallet.

I'm confused by your logic and reasoning here... You can totally using existing seed phrases/master public keys to create a MultiSig wallet. Yes, it will generate different keys/addresses, but you can still create a MultiSig address using them.

What do you mean by a "single pubkey" wallet? Do you mean a wallet that has been imported using WIF keys? Because they don't even have master public keys... and Electrum doesn't even support creating single address MultiSigs... it has to be done using seed phrases or master keys.

You'll also add more risk: instead of one private key (or seed phrase), you'll need to keep multiple keys/seeds secure. Keeping them in the same place makes multisig useless, so you'll need multiple safe locations and make sure you don't lose them.

If you have two single pubkey wallets already, and you think you can use the wallet to generate multisig wallets to setup a multisig wallet, it is not possible. This is why:

If you import the seed phrase of the two wallets to setup a multisig wallet, each will generate different keys and addresses. If you also import the two old single pubkey wallet master public keys to want to setup the multisig wallet, it will not work. Which means it is not possible to use existing single key wallet to generate multisig wallet.


You can easy just generate new seed phrases for the multisig wallet which is the best, and transfer your funds from the single key wallet to your multisig wallet just easily.

Know that once Pay-to-taproot (P2TR) is activated before the end of this year, you can as well move to P2TR to take advantage of both multisig and low fee.

Multisig wallet is one of the safest wallet, if only a single private key is revealed to a hacker, it will still be very impossible (while making sure no public key of others is revealed) for the hacker to know the other private keys. You can even combine two hardware wallets to setup multisig wallet which also makes the private key to be offline also, this is the most secure wallet.

mocacinno is correct... you cannot convert an existing wallet so that it is MultiSig and has the same addresses as the existing wallet. Once you create the MultiSig wallet, the addresses will be different.

However, you can use your existing wallet as one of the parts of a MultiSig setup.

Yes. You need at least another one other seed or master public key.
Not necessarily. Multisig serves as a system to allow the users to specify the conditions for a transaction to be valid, and in this case the number of signatures from unique parties for a transaction to be valid. It doesn't make it more secure if you're going to be signing or exposing the keys to a single point of failure, eg. signing them on the same computer or generating the seeds on the same computer. You're also having a much larger transaction size due to the inclusion of the redeem script and signatures.

You mean: is it possible to use an existing wallet and convert it to a multi sig wallet while still deriving the same addresses? In that case: no, not possible... You'll need to create a multisig wallet from scratch, it'll be a brand new wallet and won't include the same addresses as your original wallet.

As for your question wether or not it's more secure: depends on your usecase... It can be more secure, but it doesn't have to be.

Is it possible to convert a 'normal' electrum wallet to multi-sig?

Also, is multi-sig more secure?