TL;DR: On 15 July, unleaded (91) ran a typical 161.2 c/L in postcode 4106 (Rocklea, Salisbury, Moorooka) — 8 servos — and a typical 199.9 c/L in 4178 (Wynnum West, Hemmant, Lytton) — 5 servos. That is a 38.7 c/L gap across the metro on one day. Metro-wide the typical postcode sat at 168.9 c/L. Fill a 50-litre tank on the dear side instead of the cheap side and you pay about $19.35 more in one hit.
I run dual-fuel LPG in an old Commodore, so unleaded is not my tank. But 91 is what most of you are buying, and I drove a courier route across the southside for twenty years, so I know which corners the map says are cheap and which ones quietly ride the top. Opinions do not fill a tank. So we counted it.
The claim
Everyone reckons their servo is a rip and the next suburb over is cheaper. Fair enough. The question is whether the map backs it, and by how much, on a real day.
What we checked
Every price here is the Queensland Government price feed — the price each servo reported charging, not a driver’s guess at the bowser.
We took every servo within 30 km of the Brisbane GPO — 473 of them — and for each one carried its most recent posted unleaded price forward to 15 July. To keep that honest we only counted servos that actually reported a price in the trailing 30 days, so nothing is carried forward from months back; 438 of the 440 in the count repriced inside that window. Then, for each postcode, we took the middle price of its servos. That is the typical level for the area on the day, not the cheapest one servo on its best morning.
The servo records here do not carry a suburb name, so we grouped by postcode and put the suburb names on afterward from the standard Australia Post postcode list. A postcode can cover a few suburbs, so read these as postcodes with names attached, not gospel suburb borders. We also dropped any postcode with fewer than four reporting servos — one lazy or one aggressive operator swings a two-servo postcode too far to trust. That leaves 47 postcodes solid enough to rank, and 59 thinner ones left out.
One check on our own working, before we go further: take the middle of those 47 postcode medians and you get 168.9 c/L — the same figure as the middle of all 440 servos taken straight. The postcode grouping does not tilt the metro read, it just sorts it by area.
What the data shows
The cheap end is the inner south, and it is not close. Median unleaded, 15 July, servo count in brackets:
- Rocklea / Salisbury / Moorooka (4106) — 161.2 c/L (8 servos). Cheapest in the count.
- Kingston / Woodridge / Logan Central (4114) — 162.9 c/L (13 servos).
- Murarrie / Cannon Hill / Hemmant-W (4173) — 162.9 c/L (5 servos).
- Kedron / Gordon Park / Chermside-W (4031) — 164.9 c/L (5 servos).
- Loganholme / Tanah Merah / Cornubia (4129) — 165.4 c/L (4 servos).
That whole run down the M1 and the Beaudesert Road corridor sat a good 4 to 8 cents under the 168.9 metro middle, and better than 30 cents under the dear end. Big sites, clustered close, and the prices sit low. The feed shows the prices, it does not show the motive, so I will leave the why to the servos.
Now the ones that were charging the top of the range on the day:
- Wynnum West / Hemmant / Lytton (4178) — 199.9 c/L (5 servos). Dearest in the count.
- Kallangur / Murrumba Downs / Dakabin (4503) — 194.9 c/L (10 servos).
- Clontarf / Margate / Woody Point (4019) — 189.9 c/L (7 servos).
- Park Ridge (4125) — 185.9 c/L (4 servos).
- Marsden / Crestmead / Waterford West (4133) — 184.9 c/L (4 servos).
Bayside east and the northern fringe out past Kallangur ran dear. Every one of those has four or more servos behind the number, so it is not one rogue operator dragging a thin postcode — it is the area sitting high on the day.
The verdict
Inner south cheap, bayside east and northern fringe dear — on this day. If you were near Rocklea, Woodridge, Cannon Hill or Kedron on 15 July, you were sitting in the good part of town. If you were around Wynnum West, Kallangur or Clontarf, the servo on your corner was charging near the top of the range.
One honest wrinkle on the dear end: Clontarf (4019) came 3rd-dearest on unleaded at 189.9, but only mid-pack on diesel at 198.9. Diesel does not ride the unleaded cycle, so that gap says 4019’s unleaded dearness is partly the cycle sitting high there on the day, not the area being structurally expensive. The extremes are more solid than that — 4106 was cheapest and 4133, 4503 and 4125 were among the dearest on both unleaded and diesel, so the cheap-inner-south, dear-fringe pattern is real beyond a single fuel.
So what for you
The 38.7-cent gap is the whole point, and it is worth being clear about what it is: it is how far apart two ends of town sat on the same afternoon. It is a different thing from the cycle — the up-and-down swing a single suburb rides across a month, which our cycle post clocked at about 45 c/L. One is distance across the map, the other is distance across the calendar, and they are not the same number.
On a 50-litre fill that 38.7-cent gap is about $19.35 between the cheap side of town and the dear side on the same day. You do not have to drive across the city for it either — the trick is not “always go to Rocklea”, it is knowing which servos near you are on the cheap side of the line and which ones are riding the top. And within a single cheap postcode the servos still spanned up to about 40 cents apart, so a postcode median points you at the right area, not the right bowser. Pinly Fuel shows you the price at every servo around you off the QLD Government feed, so you can see the across-the-road spread before you pull in, not after.
The honest limit
This is one day’s snapshot, not a standing ladder. It is the last posted price carried forward to 15 July — a level, not a live promise about the price on the bowser this afternoon. Two more things to keep it straight. The four-servo cut is a judgement call: 59 thinner postcodes are left out, and a looser cut would reshuffle the tails, so this ranks areas with enough servos to trust, not every corner of the map. And a couple of the dear entries may just be sitting near a cycle peak rather than being dear all year. The solid read is the shape: inner south cheap, bayside east and northern fringe dear, corroborated on diesel at both ends. Use it to know which side of town wins, then check the live price before you fill.
This one is unleaded only. If you run a ute, the cheap zones are not the same — diesel sits on its own cycle and its own geography, and Tom has the diesel geo-guide coming for that.
— Shane