This guide explains Safe Multisig contract nonces and what they mean for transaction execution.
Understanding Safe Multisig Nonces
Safe Multisig contracts implement a nonce system to ensure each transaction can only execute once, preventing replay attacks. The Safe Multisig nonce functions identically to the nonce used by externally owned accounts (EOAs).
When two Safe Multisig transactions share the same nonce and are awaiting execution, they conflict with each other because only one can successfully execute, which invalidates the other.
Nonce Increment Behavior
When a Safe Multisig transaction is executed, the current Safe Multisig nonce increases by 1. All subsequent transactions must use this new, incremented nonce.