Overtaking Rules in Australia: Merging and Lane Changes

Photo: JustARandomEditor1, CC BY-SA 4.0, via Wikimedia Commons

Overtaking rules in Australia come from the national road rules, so they are almost identical in every state: overtake on the right, never across a continuous line on your side, and never over the speed limit. Merging and lane changes come down to giving way to the right vehicle. This explainer covers when you can and cannot overtake, passing on the left, the zip merge, and what to do when you are being overtaken.

Key facts

You must not go over the speed limit to overtake (NSW, WA).
Do not overtake across a continuous dividing line, or without a clear view of oncoming traffic.
Do not overtake a vehicle that is stopping or has stopped at a pedestrian crossing, children’s crossing, intersection or railway crossing.
Overtaking on the left is allowed only in a few cases (below).
Changing lanes: give way to vehicles already in the lane you are moving into.
Zip merge: where two lanes become one with no markings, give way to the vehicle ahead.
Keep left unless overtaking: on multi-lane roads over 80 km/h in NSW, Victoria, Tasmania, the ACT and the NT, or 90 km/h and above in WA, and wherever a sign says so.

When you must not overtake

Across a single continuous dividing line, double continuous lines, or a continuous line closer to you.
When you cannot see far enough ahead, such as approaching a crest, curve or blind bend.
When a vehicle is stopping or has stopped at a pedestrian, children’s or railway crossing, or at an intersection.
Where the road narrows.
Where there is a No overtaking sign, including on a bridge with a No overtaking or passing sign. There you must also give way to oncoming vehicles (NSW).
When a long vehicle showing “Do not overtake turning vehicle” is turning. Do not pass on the side it is turning to (NSW).

Intersections, rail crossings, shopping centre entrances and pedestrian crossings are never good places to overtake (VIC). For what each line allows, see Australian road markings and lane lines.

How to overtake safely, step by step

Look ahead. Make sure there is enough clear road to pass and get back safely. The faster the traffic, the more distance you need.
Check side roads and other lanes for anything that could move into your path.
Check your mirrors and blind spot. Motorcycles and bicycles hide easily, and someone may be overtaking you.
Indicate for long enough to warn others.
Pass within the speed limit.
Move back only when you can see the vehicle you passed in your rear-view mirror, and indicate as you return.

If you have any doubt, wait. Overtaking is one of the most dangerous manoeuvres (WA).

Overtaking on the left: the only times it is allowed

Under the NSW handbook, you may pass on the left only when the vehicle you are passing:

is waiting to turn right or make a U-turn from the centre of the road, or
is stopped, or
is on a multi-lane road and it is safe.

To get past a vehicle turning right, NSW says you can:

use the left lane
drive on or outside an edge line for up to 100 metres
use a bus, transit or truck lane for up to 100 metres
use a bicycle or tram lane for up to 50 metres

WA also allows passing on the left when a police officer or other authorised person directs you to. Victoria allows it on a road without marked lanes only when the vehicle ahead is turning right or is stationary.

Bicycles may overtake vehicles on the left. Check your left mirror before turning.

Keep left unless overtaking

State	When you must keep out of the right lane
NSW, VIC, SA, TAS, ACT, NT	Multi-lane roads with a limit over 80 km/h, or where a Keep left unless overtaking sign is shown
WA	Roads with a limit of 90 km/h or higher, or where a sign is shown
QLD	Check your state handbook

Exceptions (NSW, VIC and WA lists):

you are overtaking, turning right or making a U-turn
you are avoiding an obstruction
traffic in the other lanes is congested
the left lane is a turning lane or a special purpose lane, such as a bus or bicycle lane, and you are going straight

On a road without marked lanes, keep as far left as you can. If you are driving slowly, pull well over to let others pass (WA).

Changing lanes

Check your inside and outside mirrors.
Indicate early enough to warn others. The faster you are going, the longer you should signal (WA).
Look over your shoulder to check the blind spot.
Watch for anyone else moving into the same lane.
Give way to vehicles already in that lane, and move only when it is safe.
Cancel your indicator once you have moved.

WA Drive Safe advises never changing lanes while going through, or approaching, an intersection, and never across a continuous lane line. If someone signals to move into your lane, be courteous and let them in.

Merging: lane ends versus zip merge

Your lane ends and you cross a lane line

If your lane is ending and you must cross a broken line, or a merge line, into another lane, give way to vehicles already in that lane (NSW, ACT). This is how most motorway on-ramps work. Slow down, find a gap and move across.

Two lanes become one with no line (zip merge)

If the lanes merge and the road markings stop, give way to the vehicle that is ahead of you. NSW calls this a zipper merge, and the ACT handbook says the vehicle ahead has right of way. On a WA freeway, give way to another vehicle if any part of it is ahead of yours.

When a bus pulls out

In NSW, if you are in the left lane and a bus showing a “Give way to buses” sign is indicating right to pull out from the kerb in front of you, you must give way to it. WA has a similar rule in built-up areas.

When you are being overtaken

Do not speed up while the other vehicle is passing (NSW, WA, TAS, NT).
Do not drive in a way that stops someone overtaking you (TAS, WA).
Stay in your lane, keep left and leave room for them to pull back in.
Being overtaken by a road train (NT): keep your speed and stay on the road. Slow down only once it moves out to pass.

Overtaking long vehicles, road trains and cyclists

Long vehicles: trucks, buses and cars towing caravans need far more time and road to pass. Vehicles 7.5 metres or longer make wide turns and may legally cross a continuous lane line to turn (WA).
Road trains (NT): do not move back in until you see both of the road train’s headlights in your mirror. See sharing the road with trucks, buses and road trains.
Overtaking lanes (NT): stay in the left lane unless you are overtaking. Where the overtaking lane ends, indicate and give way to any vehicle in the other lane.
Motorcycles: give them as much room as a car (NSW).
Cyclists: leave at least 1 metre at 60 km/h or less, and 1.5 metres above that. See minimum passing distance for cyclists.

Common questions

Can I speed up to overtake?

No. You must stay within the speed limit while overtaking. If you cannot pass within the limit, do not overtake.

Is undertaking (passing on the left) legal on a freeway?

On a multi-lane road, passing on the left is allowed when it is safe. You still must not sit in the right lane on fast roads unless you are overtaking or one of the exceptions applies.

Who gives way when two lanes merge into one?

With no lane line: the vehicle behind gives way to the vehicle ahead. With a line to cross: the vehicle crossing the line gives way.

Do I need to indicate when merging?

Yes. You must indicate when changing lanes or merging, and turn the indicator off afterwards (NSW).

Can I do a U-turn across double lines in the NT?

No. The Northern Territory’s road rules ban U-turns across a single continuous centre line and across double centre lines, even when one of the pair is broken. A No U-turn sign also bans it, and at traffic lights you need a U-turn permitted sign. Where a U-turn is allowed, start from the lane nearest the centre, signal, and give way to all vehicles and pedestrians.

Can I overtake a car stopped at a pedestrian crossing?

No. Stop behind it. There may be a pedestrian you cannot see.

How do I join a motorway safely as a learner?

Match your speed on the ramp, indicate, give way to vehicles already in the lane and merge into a gap. See learners on motorways and freeways.

Sources

Transport for NSW, “Road User Handbook” (nsw.gov.au)
Department of Transport and Planning Victoria, “Road to Solo Driving” (transport.vic.gov.au)
Department of Transport and Major Infrastructure WA, “Drive Safe: A handbook for Western Australian road users” (transport.wa.gov.au)
Government of South Australia, “The Driver’s Handbook”, February 2026 (mylicence.sa.gov.au)
Department of State Growth Tasmania, “Tasmanian Road Rules, Version 2.1” (transport.tas.gov.au)
Access Canberra, “ACT Road Rules Handbook” (accesscanberra.act.gov.au)
Northern Territory Government, “NT Road Users’ Handbook” (nt.gov.au)
Northern Territory Government, “Changing lanes and turning” (nt.gov.au)

Overtaking Rules in Australia: Merging and Changing Lanes