A person may be released on bail on their own undertaking, where they sign the agreement and personally guarantee to appear and comply with the conditions of the bail agreement. Sometimes, a guarantor is required.

A guarantor enters into a separate agreement known as a guarantee of bail, in which they guarantee that the person who is released on bail will comply with the bail agreement (or with specified conditions of the bail agreement). The guarantor may be required to forfeit a sum of money if the person on bail fails to comply with a term or condition of the bail agreement [Bail Act 1985 (SA) s 7].

A guarantor must be at least 18 years of age [s 7(6)].

If a guarantor knows, or reasonably suspects, that the person on bail has breached a term or condition of their bail agreement, the guarantor must take reasonable steps to notify the police. Failure to do so may result in a fine as well as forfeiture of a sum of money [s 17A].

A guarantee of bail is a serious, binding obligation and a guarantor will only be released from an obligation in extreme circumstances. A guarantor can apply to the court to vary the conditions of the guarantee of bail or to revoke it at any time [s 7(4)].