Speed Limits

NOTE: If you are the holder of a learner's permit or a provisional licence, you may be limited as to the speed at which you are permitted to drive. Refer to the Drivers and Licensing section for information about special speed limits that apply to permit and some licence holders.

The speed limit that applies to a road or road-related area is the maximum speed you are allowed to drive a vehicle.

You should only drive to the speed limit if it is safe to do so. It may not be safe to drive to the speed limit in certain conditions, for example, due to poor weather or heavy traffic or the condition of the road. In these situations, you must slow down to a speed that is safe for the prevailing conditions.

How is the speed limit set?

Within South Australia (and in fact throughout Australia) the maximum default speed limit outside a built-up area is 100 km/h. The maximum default speed limit in a built-up area is 50 km/h. Unless a road sign or a licence condition indicates otherwise, these are the general maximum speeds at which you are allowed to drive. The circumstances under which these limits might be varied are set out below.

Speed limit signs

The speed limit on a section of road may be varied from the above default speed limits by speed limit signs.

Higher speed limits

Outside a built-up area, some roads may have a speed limit of 110 km/h shown by speed limit signs. You may travel up to this higher speed provided your driving licence permits you and it is safe to do so. Learner and provisional drivers, for example, must not travel at this higher speed.

Also the maximum speed limit for a vehicle that exceeds a GVM of over 12 tonne or a bus GVM over 5 tonne is 100 km/h, except in the case of road trains where a speed limit of 90 km/h applies on most roads. Refer to the Heavy Vehicle Driver's Handbook for more information on heavy vehicles.

In built-up areas, some roads may have a higher speed limit (for example 60 km/h or 80 km/h) shown by speed limit signs.

Lower speed limits

Any road may have a speed limit lower than the default speed. This will be shown by a speed limit sign. This lower speed limit applies to the section of road marked by the signs, and you must not exceed this lower speed limit.

Some common examples of reduced speed limits are:

25km/h speed limits

• Between school crossing (koala crossing) when the lights are flashing as indicated by a Children's Crossing sign.
• When a child is within a school zone, which is formed between a school zone sign and end school zone sign. This applies whenever a child is on the road, footpath, median strip, or even on a bicycle including outside of school hours.
  A ‘child’ means a person less than 18 years of age, and includes a student of any age wearing a school uniform.
  A school zone is also marked with zigzag lines on the road where practicable, to show that you are approaching a school zone.
• You must not exceed 25 km/h when passing, in either direction, a school bus that has stopped for the purpose of setting down or picking up children.
• When passing a stationary emergency services vehicle that has its blue and/or red lights flashing (see below).

40 km/h speed limits

• Some built-up areas (for example residential areas) have a speed limit of 40 km/h indicated by signs on all roads leading into that area.
• On the approach to wombat pedestrian crossings indicated by signs.

General safety speed limits

You must slow down to 25 km/h or a lower speed if required when passing an emergency vehicle that is stationary and displaying blue or red flashing lights or between two sets of flashing blue or red lights.

An emergency services vehicle includes:

• ambulance
• fire service vehicle
• State Emergency Service vehicle
• police.

* For more information about expiation fees and demerit points visit The Penalties page.

Please note that heavy penalties apply to trucks and buses speeding on the South Eastern Freeway descent.