Bomaderry Diesel Runs 19 Cents Under the NSW Average While Every Singleton Servo Charges 234.9
New South Wales has handed me a complete lesson on competition this morning, and it only needs two towns to teach it. In Bomaderry on the south coast, four servos are selling diesel at anywhere between 215.5 and 236.9 cents a litre. That is a spread of 21.4 cents within a few minutes of driving. Up in the Hunter Valley, the three servos reporting in Singleton are all charging 234.9. Not roughly the same. Exactly the same, down to the tenth of a cent.
As of 8:11am AEST on 15th Aug 2026, the NSW diesel average sits at 246.9 cents a litre, down 2.0 cents on yesterday. Bomaderry's average of 227.3 comes in nearly 20 cents under the state figure, and its cheapest board is more than 31 cents below it. Same fuel, same bowsers, same wholesale market. So why do the two towns behave so differently?
Bomaderry shows competition doing its job
Economists call what Bomaderry is displaying price dispersion, which is simply the same product selling at different prices in the same area at the same time. You might be wondering how a 21 cent gap survives when the servos are practically neighbours. The answer is that not every driver compares. Plenty of motorists fill up at whichever servo happens to be on their side of the road, and operators know it. The servo charging 236.9 is banking on passing trade. The one at 215.5 is chasing volume, hoping a steady queue of savvy locals makes up for the thinner margin on each litre.
Think of it this way. Two supermarkets in the same suburb can sell the same loaf of bread at different prices for years, because only some shoppers check both. Fuel works the same way, except the price is posted on a giant sign by the road, which makes shopping around far easier if you actually look at it.
Singleton shows the opposite force
Now for the strangest number in this morning's data: a spread of zero. All three Singleton servos are posting 234.9. That is not a coincidence, and it is not a conspiracy either. It is what economists call tacit price matching, and it thrives in small markets. Each operator can see the competitors' boards from the highway. If one drops a cent, the others match it within hours, so nobody wins customers and everybody earns less per litre. After that plays out a few times, the sensible move is to sit at the same number and hold. In a mining region where the utes and trucks fill up regardless, there is little reward for starting a price battle.
Western Sydney sits in between
The competitive middle ground is on display across western Sydney. Fairfield is averaging 230.4 cents for diesel and Smithfield 231.0, both comfortably under the state average. Greenacre averages 235.3, higher again, but its cheapest servo is at 226.7, a gap of more than 19 cents inside the one suburb. A suburb's average can hide a bargain, which is why the price board matters more than the postcode.
The same contrast appears on the industrial coast. Mayfield in Newcastle carries an 18.4 cent spread, while Port Kembla servos sit within 1.6 cents of each other. That is Singleton's small market behaviour in miniature.
What this means for your tank
The key factor here is that spreads are where the savings live. In Bomaderry, choosing the right servo instead of the wrong one saves 21.4 cents a litre, about $12.84 on a 60 litre ute tank. In Singleton it saves you nothing, because there is no gap to exploit. Before you fill up, check the current diesel prices to see which kind of market your suburb is running today, and the price trends page if you want to judge whether waiting a day might help.
NSW is at least drifting the right way. The 2.0 cent easing compares with Victoria down 2.6 to 244.0, while my own South Australia rose 3.5 to 249.6 and Queensland added 1.6 to reach 248.0.
Understanding why a spread exists, or why it does not, tells you whether shopping around will pay in your area. In a town like Bomaderry it pays handsomely. In a town like Singleton, the market has already made that decision for you.
