The median unleaded price across Western Australia is 197.2 c/L and diesel is 240.4 c/L, as at 16 August 2026. Unleaded is 4.8 c/L cheaper than a week ago. That makes WA the cheapest jurisdiction in the country, 3.7 c/L below the middle of the pack.
Every figure below is the median price across all reporting Western Australia sites, blended between Greater Perth and the rest of the state by population. A median, not an average, so a few sites pricing far above the rest cannot drag the headline up.
| Fuel | Median c/L | vs a week ago |
|---|---|---|
| Unleaded 91 | 197.2 | -4.8 c/L |
| Diesel | 240.4 | -3.9 c/L |
Diesel is running 43.2 c/L above unleaded in Western Australia. Diesel does not follow the discounting cycles petrol does, so this gap moves with wholesale costs rather than with retailer pricing rounds.
Over the 34 days since 14 July 2026, unleaded in Western Australia has ranged between 173.2 and 215.4 c/L, a spread of 42.2 c/L. The typical day-to-day move is 3.1 c/L, and the largest single day move was +18.2 c/L on 5 August 2026.
Regional Western Australia is paying 15.8 c/L more than Greater Perth today. Across the whole window the gap has averaged 7.7 c/L over 34 days. Greater Perth is the ABS Greater Capital City area; everything outside it counts as regional.
| Area | Unleaded c/L | Sites reporting |
|---|---|---|
| Greater Perth | 193.9 | 478 |
| Rest of WA | 209.7 | 461 |
Sub-averages as at 16 August 2026.
Yes, and it runs on a weekly clock. Across 4 weeks of our own WA readings, Wednesday is the day prices jump: unleaded has risen an average of 8.8 c/L on a Wednesday, against small changes on every other day. That matches what the ACCC records for Perth, which it describes as weekly with the spike on a Wednesday. If you can choose when to fill up, the days before Wednesday are the cheap end of that cycle.
| Day | Average change c/L |
|---|---|
| Sunday | -0.6 |
| Monday | -0.2 |
| Tuesday | +2.1 |
| Wednesday | +8.8 |
| Thursday | -3.7 |
| Friday | -0.2 |
| Saturday | -1.9 |
Mean day-over-day change in the WA unleaded median, by day of the week, over 33 consecutive-day pairs. A short window: treat it as this season's pattern rather than a permanent one. Cycle lengths quoted above are the ACCC Petrol Price Cycles in the 5 Largest Cities; the weekday figures are our own.
The Australian Institute of Petroleum publishes a terminal gate price for Western Australia: what fuel costs leaving the terminal, before a retailer's own costs and margin. On 14 August 2026 that was 191.1 c/L for unleaded, against a pump median of 197.2 c/L - a gap of 6.1 c/L, and 11.1 c/L on diesel. That gap is not profit. It covers freight from the terminal, the site's own running costs, and whatever margin the retailer is taking.
The wholesale figure is published on weekdays and normally runs a day or two behind the pump figure, so the two dates above will rarely match exactly. The full build-up from barrel to bowser.
Every figure on this page comes from WA FuelWatch, run by the WA Government. It is a next day price schedule rather than a live feed - FuelWatch publishes tomorrow's prices each afternoon, by 2:30pm AWST. We read it twice a day, take the median across the sites reporting, and publish it unaltered. We do not model, smooth or forecast the price.
That data is published under CC BY 4.0.
Fuel excise is a Commonwealth tax, so it is identical in Western Australia and everywhere else. It returned to 53.7 c/L on 3 August 2026, worth up to about 18.8 c/L at the pump once GST is applied. Differences between states come from freight, competition and local costs, never from tax. What fuel excise costs per tank.
The national tracker: all eight jurisdictions, every fuel type, and what makes up a litre.
How these figures are derived: pricing methodology. Ways to pay less: save on fuel.