Perth Unleaded Stalls at 184.6 as the Cheap Tuesday Floor Lifts 21 Cents in a Month
According to pricing data collected at 2:10pm AWST on Saturday 25th Jul 2026, the average of unleaded petrol prices across 501 metropolitan Perth servos sits at 184.6 cents. Wednesday's hike day peak was 184.7. Four days after the increase, Perth motorists have got back one tenth of a cent, which in the city with the most predictable petrol cycle in the country is not how the week is meant to go.
Breaking down this week's cycle
The mechanics here are usually reliable. Prices grind down through the back half of the week, bottom out on Tuesday, then lift on Wednesday morning.
This week followed the script for one day. The metro average bottomed at 169.7 cents on Tuesday 21st Jul, then rose 15.0 cents overnight to 184.7 on Wednesday 22nd Jul. After that the decline stopped almost before it started: 183.9 on Thursday, 183.3 on Friday, and back up to 184.6 today.
Historical data suggests that is not how the week normally ends. Each of the previous three cycles had Saturday sitting well below the Wednesday peak. In the week beginning 15th Jul the metro average eased from 175.3 to 173.0 by Saturday, and the week before that prices went from 172.9 on Wednesday to 165.6 by Saturday, a retreat of 7.3 cents. This week the equivalent figure is 0.1 cents, so anyone who waited out the weekend for a better board has nothing to show for it.
The floor is moving, and it is moving up
Perth's Tuesday trough, the single cheapest day of the cycle, has been climbing all month. On 30th Jun the metro average bottomed at 148.4 cents. On 7th Jul it was 163.2. On 14th Jul it eased slightly to 162.5, then on 21st Jul it reached 169.7. That is 21.3 cents added in four weeks to the one day of the week when Perth drivers are supposed to be getting a break.
The peaks moved almost in step. Hike day averages have gone from 164.0 cents on 1st Jul to 184.7 on 22nd Jul, an increase of 20.7 cents. When both ends of the cycle lift by roughly the same amount, the wholesale cost base is a more likely explanation than anything the retailers are doing differently at the board. The cycle is working. It is just working from a dearer number each week.
Where the value sits across the metro
The spread between the cheapest and dearest metro pump today is 33.2 cents, worth close to $20 on a 60 litre fill.
Kwinana Beach again leads the cheaper suburbs, averaging 175.6 cents across its five sites with a Caltex pump at 168.7. That is the cheapest price open to any motorist in the metro area. Two warehouse sites at Casuarina and Perth Airport are posting 166.7, though you need a membership to use them.
The northern corridor is holding up, with Neerabup at 177.3 and Wanneroo at 177.4 across eight servos. Landsdale averages 178.6 with a low of 169.3, matched exactly by Beckenham in the south east. Bassendean at 179.1 and Forrestfield at 179.4 are the only other suburbs still under 180.
At the dearer end, Muchea averages 192.9 cents, Mandurah 189.0 and Kewdale 188.3. Filling in Mandurah instead of Kwinana Beach costs about 13 cents a litre more for the same fuel.
The other fuels have been quieter. Diesel averages 224.7 cents with the cheapest diesel prices at 201.0, premium 95 sits at 200.3 and premium 98 at 209.2. LPG is the outlier at 156.0.
What it means for next week
Tuesday 28th Jul is still the day to fill in Western Australia. On the current trend it will probably land nearer 170 cents than the 148 that was there a month ago. Our best time to fill up guide tracks the cycle for every capital, and the price trends page shows how the WA base has shifted through July.
Perth's cycle is intact and its timing has not moved. What has moved is the floor underneath it, up 21 cents since June, and that will still be the case once this week's stall sorts itself out. Knowing when to fill still saves money here. It just saves less of it than it did four weeks ago.
