Multisignature (Multisig)
Abbreviation: Multisig
Pronunciation: MUL-tee-sig-nuh-cher (MUL-tee-sig)
Also known as: Multisignature, Multi-signature, Multisig
Definition
Multisignature requires more than one approved cryptographic signature to authorize a transaction under a defined rule, such as two of three keys.
Overview
What it means
Multisignature requires more than one approved cryptographic signature to authorize a transaction under a defined rule, such as two of three keys. It can distribute control across people or devices instead of relying on one secret.
How it works
On Bitcoin, multisignature conditions can be expressed through script and different spending constructions; smart-contract chains can implement their own multisignature account logic. The wallet coordinates proposals, signatures, fees and execution. Signers should independently verify recipient and amount rather than merely approve a hash.
Understanding the technical details
The M-of-N rule should be chosen around realistic failure modes: loss of one device, departure of one employee, compromised workstation and emergency recovery. A two-of-three setup can protect against one stolen key and tolerate one lost key, but only if independent parties really control the devices. Test spending and recovery with small amounts before depositing major treasury reserves. For contract-based multisig, review upgrade authority and execution delays as additional privileged paths.
Additional protocol context
Multisig should not be confused with ordinary workflow approval. Several interface approvals may lead to one provider-controlled signature, while a cryptographic threshold can prevent any single key from authorizing. Different implementations also vary in privacy, cost, recovery, and compatibility.
Designers should choose participants, threshold, independence, replacement, and emergency procedures based on threat and availability needs. Signers must verify the same transaction intent. Documentation should identify where enforcement occurs and who can change it. Regular tests should confirm that the threshold works under normal and degraded conditions.
Common failures and limitations
Two devices controlled by the same compromised operator do not provide genuine organizational separation. Lost keys, unavailable cosigners, buggy multisig contracts and poorly stored recovery material can prevent legitimate access.
Related concepts
Crypto Wallet, Private Key, Seed Phrase.
Further reading
Example
A nonprofit stores reserve funds under a two-of-three policy: the finance lead and one board member must approve transfers, with a third signer available for recovery. A single stolen laptop cannot independently send the reserve.
Comparison
Multisig uses several signatures for one authorization rule. Multi-factor authentication protects account access with different factors; it does not necessarily change the signatures required by a blockchain.
Key Takeaway
Two devices controlled by the same compromised operator do not provide genuine organizational separation.
Sources
- NIST Documentation: Cryptographic Standards And Guidelines — NIST (2026-07-30)
- NIST Key Management Guidelines — NIST (2026-08-02)