Cheapest Diesel Fuel Prices in Western Australia Today

As of 5 July 2026, the cheapest Diesel in Western Australia is 167.90 cents per litre in Kelmscott. The state average is 194.50 c/L across 316 stations. Prices update daily via FuelWatch from official government data.

FuelTrack tracks prices at 316 petrol stations across 118 suburbs in Western Australia. Prices are sourced from official government fuel price monitoring schemes and updated daily via FuelWatch.

Based on the past 4 weeks, Mondays tend to have the cheapest Diesel prices in Western Australia, averaging 175.40 c/L. Wednesdays tend to be the most expensive at 182.20 c/L – a difference of 6.8 cents. Patterns vary by suburb, so check your local area for the most accurate timing.

Fuel excise is the federal tax built into the price of every litre of petrol and diesel. It normally rises twice a year in line with inflation, and in early 2026 it sat at 52.6 cents a litre. When conflict in the Middle East pushed oil prices higher, the government brought in cost-of-living relief: from 1 April it roughly halved the excise, taking about 32 cents a litre off the bowser price. On 20 June that relief was extended into July but tapered to a 16 cent cut, lifting the excise to 36.6 cents, so pump prices rose at the start of July. The reduced rate runs until 2 August. From 3 August the full 52.6 cent excise returns, and because GST is charged on top of it, that's expected to add about 18 cents a litre at the pump, or roughly $9 on a 50-litre tank, unless retailers absorb part of the increase. A routine inflation adjustment in early August nudges the rate a little higher again.