1. Cars and Driving
  2. Overview
  3. Road safety

Is driving beneath the speed limit illegal?

Slow driving
Slow driving

Last updated: 14 August 2024

While many drivers are aware of the dangers of driving too fast, some don’t see the harm in driving too slowly. While you're more than likely to gain the ire of drivers behind you, remember that driving under the speed limit is legally fine, but driving excessively slowly can land you in a bit of hot water.

Driving slowly

According to NSW Road Rules 2014 - Rule 125, “a driver cannot unreasonably obstruct the path of another driver or a pedestrian.” This means that if a driver is traveling too slowly for the conditions and causing an obstruction, they could face a fine of up to 20 penalty units, which are currently valued at $110 each in NSW. This results in a potential fine of up to $2,200. For example, traveling at 20 kilometers per hour on a road with a speed limit of 80 kilometers per hour might be considered driving “abnormally slowly” and could lead to such a fine if it obstructs other drivers.

It’s important to note that while the general rule prohibits causing obstructions, there are specific situations where driving below the posted speed limit might be considered reasonable and not constitute an obstruction. For instance:

  • Adverse weather conditions: A driver might be driving slowly during heavy rain, snow, or dense fog, but this is at the discretion of the driver and what they judge to be a safe speed given the visibility and road conditions, 
  • Heavy vehicles: A heavy vehicle might travel below the posted speed limit when ascending or descending a hill due to its capabilities. 
  • Cyclists: A cyclist may ride slower than the posted limit based on their capability and safety considerations.

Keeping left

Drivers are to keep to the left on a multi-lane road where the speed limit is over 80 kilometres per hour and are only allowed to drive in the right lane in certain circumstances, such as:


  • Overtaking
  • Turning right
  • Making a U-turn from the centre of the road
  • There is a ‘Left lane must turn left sign’ or left traffic lane arrows apply and the driver is not turning left
  • The driver is required to drive in the right lane if traffic signs require a particular kind of vehicle to drive in the marked lane indicated by the signs.
  • Avoiding an obstruction
  • Traffic in every lane is congested
  • The right lane is a special purpose lane in which the driver is permitted to drive
  • There are only two marked lanes and the left lane is a slow vehicle turn out lane.

If a ‘Keep Left Unless Overtaking’ sign is displayed, then you must keep left regardless of the speed limit (unless overtaking).

 

Tailgating

Tailgating is a definite no-no and Road Rules 2014 - Rule 126 make this clear: “A driver must drive a sufficient distance behind a vehicle travelling in front of the driver so the driver can, if necessary, stop safely to avoid a collision with the vehicle."

In NSW, the current penalty for tailgating is a $544 fine by way of an on-the-spot fine or penalty notice and 3 demerit points.

Check available venues and dates

Book your Safer Drivers Course today

Book course or Call 1300 696 762