Mount Gambier's Cheapest Unleaded Falls 16.6 Cents to 217.9 as Millicent Sits 18 Cents Higher
Prices lodged over the past fortnight show Mount Gambier pulling away from its neighbours on South Australia's Limestone Coast. The lowest unleaded price in town has fallen from 234.5 on 21st Oct to 217.9, while Millicent, 44 kilometres to the north west, sits on 235.9.
The figures come from South Australia's official fuel price scheme, as read at 7:45am ACDT on 2nd Nov 2026. All times are ACDT.
Nine steps in under 10 days
Five servos shared 234.5 on 21st Oct: United, Pearl Energy, Mobil, Matthews Petroleum and APCO. At 9:11am on 22nd Oct, Shell Express cut from 235.9 to 229.9, and United matched it 14 minutes later.
The town's lowest price then stepped through 227.9, 225.9, 223.9, 222.9, 221.9, 219.9 and 218.5, with rivals answering most moves within hours. Shell Express reached 217.9 at 5:40pm on 31st Oct, and EG Ampol Marketplace joined it at 9:42am on 1st Nov.
The town's cheapest unleaded was under two dollars at 199.5 in early September, then climbed 35 cents to 234.5 by 8th Oct. Today's 217.9 hands back 16.6 of those cents and is the lowest price in town since mid September.
Two prices in one town
This morning, 7 of the 15 Mount Gambier sites with a current price are on 217.9 to 219.9. The other 8 are on 229.9 to 233.9, and nothing sits in between. The split holds at short range: Shell Express is 589 metres from OTR Mount Gambier on 229.9 and 691 metres from AM/PM Bay Road on 233.9.
The Ampol group's lift on 29th Oct tested the lower group. EG Ampol Marketplace went from 219.9 to 224.9 at 6:07am. Three minutes later, Mobil and Pearl Energy cut to 219.9, and United followed at 6:45am. EG Ampol was back on 219.9 by 11:17am, five hours and ten minutes after it lifted. That rise faded faster than the same move in Tasmania and Brisbane.
Millicent moves on a different schedule
Millicent has cut too, though in step with other sites. K&S Pitstop and Millicent Roadhouse belong to a set of six that also includes two Ampol sites in Mount Gambier, among them Jubilee Highway, plus Port MacDonnell OPT and Lucindale OPT. All six cut exactly 5 cents on 19th Oct, 6 on 27th Oct and 4 on 30th Oct, within about an hour of each other each time. This is consistent with one pricing decision across the set, though the data doesn't show who makes it.
Every site moved the same 15 cents, so the gaps inside the set did not change. Millicent stayed 6 cents above Jubilee Highway and Lucindale stayed 9. Mount Gambier's lower group fell further, so Millicent's gap to the town's lowest price widened from 11.4 cents on 21st Oct to 18.0 today.
Further afield, EG Ampol Naracoorte, 95 kilometres north, is on 248.9, or 31.0 cents above the same brand in Mount Gambier. Across the border in Victoria, OTR Portland and OTR Hamilton are on 242.2, 12.3 cents above OTR in Mount Gambier.
How it compares with Adelaide
On 21st Oct, Mount Gambier's lowest price was level with the Adelaide median of 234.4. Today it is 10.5 cents under the 228.4 median across 267 Adelaide servos, and only 5 of those are below it. No other regional South Australian site matches 217.9.
What it means at the pump
On a 60 litre tank, the 16.0 cent gap between 217.9 and 233.9 in the same town is worth $9.60, so check current unleaded petrol prices before you leave. The 18.0 cent gap to Millicent is worth $10.80 if you're already heading to Mount Gambier.
Only three sites in town list E10 prices, with United on 214.5, and Pearl Energy and APCO on 217.9. United and Shell Express have diesel at 255.9, 13.0 cents under the 268.9 median across 39 Adelaide sites listing regular diesel prices.
The lower group has moved every few days, so watch price trends as well as the pump. For Limestone Coast motorists, the data shows location matters most, with 16 cents separating servos less than a kilometre apart.