Perth Diesel Drops 11 Cents Overnight While Adelaide and Hobart Climb and the 122 Cent Spread Across WA Tells the Real Story

The data from the past 24 hours reveals a notable split in Australia's diesel market that motorists should be paying attention to. Western Australia has recorded the sharpest overnight diesel decline of any state, with the average dropping 11.2 cents to 311.9 cents per litre across 792 stations. Meanwhile, South Australia climbed 5.7 cents and Tasmania pushed 6.7 cents higher.

But the headline number hides a far more interesting story. The spread between the cheapest and most expensive diesel in WA has blown out to 122.4 cents. That is not a typo. Motorists in certain Perth suburbs are paying more than $1.20 per litre more than others for the same fuel.

Where the Savings Are Hiding in Perth

A closer analysis reveals that the cheapest diesel in the Perth metro area is concentrated in a handful of southern and eastern suburbs. Forrestfield is averaging 290.5 cents across five stations, with the cheapest servo posting 278.9 cents. Kwinana Beach is similar at 295.7 cents average across six stations, though the spread within the suburb is a notable 35 cents.

Beckenham stands out as the tightest diesel market in Perth, with three stations clustered between 281.3 and 289.5 cents, a spread of just 8.2 cents. That kind of consistency is rare in a city where neighbouring suburbs can differ by 30 cents or more.

Further north, Morley tells a different story entirely. Six stations span from 279.9 to 319.9 cents, a 40 cent gap within a single suburb. Bassendean shows a similar pattern at 287.3 to 319.9 cents across four stations. The data indicates that motorists who simply pull into the nearest servo without checking prices could be paying substantially more than necessary.

The Kununurra Question

Kununurra in the state's far north is recording a staggering 104.7 cent spread across eight stations. The cheapest is posting 227.5 cents, which is actually the lowest diesel price in all of Western Australia. The most expensive in the same town is 332.2 cents. That is a $15.54 difference on a 60 litre fill.

This is worth noting because Kununurra is often cited as an example of remote area fuel premiums, but the cheapest station in town is undercutting every servo in metropolitan Perth by more than 50 cents. Distance from refineries does not explain everything.

South Australia and Tasmania Head the Other Way

While Perth celebrates lower prices, Adelaide motorists are seeing the opposite trend. South Australia's diesel average climbed 5.7 cents overnight to 317.8 cents per litre across 354 stations. Mount Gambier, the state's second largest city, is averaging 304.3 cents with the cheapest at 295.9 cents.

Tasmania recorded the steepest percentage increase at 2.16%, pushing the state average to 316.6 cents. The 73.1 cent spread across the island suggests that regional Tasmanian motorists are bearing a disproportionate share of the increase.

Interestingly, Victoria quietly dropped 4.9 cents to 312.2 cents, making it the second cheapest diesel state behind ACT at 306.4 cents. NSW fell 3.5 cents to 317.8 cents, identical to South Australia's average but trending in opposite directions.

The National Picture in Numbers

The state by state diesel averages this morning paint a clear picture of the market divide:

The Northern Territory deserves a mention for its 252.9 cent spread, the widest of any state, driven by remote community stations where diesel can exceed $3.99 per litre while Mataranka posts 285.0 cents.

What This Means for Motorists

The numbers are clear: motorists who time their fill ups strategically could save substantially. In Perth alone, the difference between Beckenham at 281.3 cents and the most expensive suburb servos at 349.9 cents is $41.16 on a 60 litre tank.

For Perth diesel drivers, the data suggests heading to Forrestfield, Beckenham, or Kwinana Beach while this pricing window holds. For South Australian and Tasmanian motorists, the trend is less encouraging, but Mount Gambier remains competitive for those in the southeast.

Check our interactive fuel map for real time pricing in your suburb.