In South Australia there are nine adult prisons (officially called correctional institutions) in operation.

While the Adelaide Remand Centre is the principal place for prisoners who are held on remand, it also holds sentenced prisoners and various of the other prisons hold both remand and sentenced prisoners.

The following is a brief description of the current capacity of, and the classes of prisoners held in, these institutions:

The Chief Executive of the Department may make rules for the prison [see Correctional Services Act 1982 s 83]. Breaches of these rules are not offences carrying punishment, see Breaches of regulations.

The Minister for Correctional Services must arrange for prisons to be inspected regularly [Correctional Services Act 1982 s 20(1)]. An inspector has an unrestricted right of entry to any part of a prison and can ask anyone any questions concerning the prison and the treatment of the prisoners [see Correctional Services Act 1982 s 20(4)].

Prisoners are entitled to make complaints to an inspector, which the inspector must investigate. The inspector must send a report on the complaint and may make recommendations to the Minister [see Correctional Services Act 1982 s 20(6)].

All judges and magistrates are entitled to inspect a prison at any reasonable time [see Correctional Services Act 1982 s 87].

Most prisoners are serving prison sentences imposed by a court. In most cases the court will also fix a non-parole period, being the period of time that a prisoner must spend in prison before release on parole [Sentencing Act 2017 (SA) s 47; see parole.

A remand prisoner is a person who has been refused bail (see questioning, search and arrest) and is being held in custody:

Remand prisoners in the metropolitan area are usually held in the Adelaide Remand Centre although over crowding means that frequently they are also held at the Yatala Labour Prison.

The status of prisoners who appeal against conviction or sentence is not quite so straightforward. The Department treats prisoners who have appealed against conviction as remand prisoners and prisoners who have appealed against sentence as sentenced prisoners. Where the appeal is against an order of a judge of he District or Supreme Court, the time spent in custody between the day the appeal is lodged and the day it is heard counts as part of the sentence (unless the person is on bail during that period) [Criminal Procedure Act 1921 (SA) s 170]. The same applies if a prisoner is appealing against a conviction or sentence of imprisonment imposed in the Magistrates Court.

Some offenders are sentenced to be detained until further order. Under section 57 of the Sentencing Act 2017 (SA) these orders can be made where the court considers that a person convicted of a sexual offence is unwilling or incapable of exercising control over his or her sexual instincts or needs care and supervision because of his or her mental condition

If the Minister for Health considers a prisoner is in need of care and control and is incapable of managing himself or herself, or his or her affairs, the prisoner is removed from prison to a special hospital for such people (for example, James Nash House) or to approved hospitals under the Mental Health Act 2009 (such as Glenside). A prisoner in such a hospital is deemed to be serving his or her sentence unless the Governor orders otherwise.