A single key is a single point of failure. Multisig requires multiple keys to authorize a transaction — eliminating the risk that one lost, stolen, or compromised key can destroy your Bitcoin.
Multisig (multi-signature) requires M-of-N keys to authorize a Bitcoin transaction. For example, a 2-of-3 setup means you have 3 keys but only need any 2 to spend. This means you can lose one key and still access your Bitcoin.
Interactive: Click keys to "sign" a 2-of-3 transaction
Select 2 keys to authorize the transaction
With a standard single-key wallet, one failure destroys everything: lost seed phrase, stolen hardware wallet, house fire, $5 wrench attack. Multisig eliminates all of these as catastrophic risks.
Store keys in different physical locations. A fire, flood, or burglary at one location shouldn't compromise your entire setup.
Use different hardware wallet brands for each key. A vulnerability in one brand doesn't compromise your security.
Regularly verify you can reconstruct your multisig and sign a transaction. Don't wait for an emergency to discover a problem.
Store the wallet configuration file (not the keys!) so you can reconstruct the multisig. Without it, even having all keys isn't enough.
Multisig isn't just a technical feature — it's a philosophy of eliminating single points of failure. The same principle applies to all of Bitcoin: no single miner, no single node, no single developer can compromise the system. Multisig extends this philosophy to your personal security: no single key, no single location, no single point of failure.