Regular keys and multi-signing

Every account starts with one key pair, the master key. It is tied to the address forever. You cannot change it. You can only switch it off.

You can add a second key, called a regular key. It signs almost everything the master key can. A common setup:

• Keep the master secret on paper, locked away.
• Use the regular key day to day.
• If the regular key leaks, take out the master key and replace the regular key.

You can also set up multi-signing. You name a group of other accounts, give each a weight, and set a target called the quorum. A transaction is valid when the signers' weights add up to the quorum. Think of a shared account that needs two of three people to approve each payment.

Both tools move power away from a single secret. That cuts both ways. Anyone whose key you add can sign for your account. Add only keys you control, or people you fully trust.

SetRegularKey. Sets, changes or removes the account's regular key. The RegularKey field is an address; omit it to remove the key. It must not match the master key. The current value shows as RegularKey on the AccountRoot.

Master-only actions. Only the master key can:

• Send the account's first transaction.
• Disable the master key (AccountSet with asfDisableMaster, value 4).
• Permanently give up the ability to freeze (asfNoFreeze).
• Send the free key reset transaction: a SetRegularKey with a cost of 0, allowed while the lsfPasswordSpent flag is off.

asfDisableMaster can be enabled only if the account has another way to sign. A regular key or a multi-signature can turn the master key back on.

SignerListSet. Creates, replaces or deletes the account's signer list.

The account cannot list itself. To delete the list, set SignerQuorum to 0 and omit SignerEntries. Deletion fails with tecNO_ALTERNATIVE_KEY if it would leave no way to sign. The 32-signer limit came with the ExpandedSignerList amendment, enabled 2022-10-13.

Costs.

• A signer list made or updated since the MultiSignReserve amendment (2019-04-17) counts as one owned object: 0.2 XRP of owner reserve. Older lists count as 2 plus 1 per signer, until replaced.
• A multi-signed transaction costs at least 10 × (1 + N) drops, where N is the number of signatures.

Read it live. account_info returns RegularKey and account_flags.disableMasterKey. Add "signer_lists": true to get the signer list. Check both on your own account after any wallet setup.