SA Fuel Prices – Week of 4 May 2026

South Australia is the cheapest state in the country for unleaded petrol right now, with metro U91 averaging 179 c/L for the week of 4 to 11 May. That's a small rise on last week, but SA still sits 2.3c below the national metro average of 181.3 c/L. Diesel drivers, though, are getting genuine relief.

SA Fuel Price Snapshot: 4–11 May 2026

Biggest Movers in SA Petrol Prices This Week

Diesel is the standout story. Metro diesel dropped 4.9c to 238.2 c/L, and rural SA saw an even steeper fall of 9.5c down to 257.8 c/L. That's meaningful money for tradies, farmers, and anyone running a diesel vehicle. The daily data shows it was a clean, steady slide all week with no reversals, which suggests genuine wholesale relief rather than a one-day blip.

Petrol grades moved the other way. U91 metro climbed steadily from 176.6 c/L on Monday to a mid-week peak of 180.4 c/L on Saturday, before easing slightly to 179.9 c/L on Sunday. The rise was gradual rather than a sudden spike.

P95 followed a near-identical path, climbing from 192.9 c/L to a peak of 196.7 c/L by Saturday before softening a touch. E10 had its sharpest jump between Monday and Wednesday, leaping from 169.1 c/L to 172.8 c/L in just two days, then levelling off.

P98 edged up throughout the week, touching 205.5 c/L mid-week before settling back to 205.1 c/L. If you're running premium, E10 remains the cheapest option in metro SA by a solid margin.

Where SA Petrol Prices Sit Right Now

The cheapest metro station recorded this week was Costco Kilburn at 166.7 c/L for U91. The most expensive was Independent Marina Fuel at 264.9 c/L. That's a 98.2 c/L gap between the cheapest and priciest stations in the same metro area. Driving an extra few kilometres to the right station can save you several dollars every fill.

Among brands, U-Go averaged 173.2 c/L for metro U91, making it the cheapest by a noticeable margin. Liberty and Mobil both averaged 174.5 c/L. At the other end, Independent stations averaged 196.7 c/L, a gap of more than 23c over the cheapest brands. BP averaged 181.9 c/L, still roughly 8c above the cheapest option.

Supply Update for SA Stations

Overall out-of-stock reports dropped from 138 to 119 station-fuels this week, which is a solid improvement. P95 availability was the biggest positive shift, with out-of-stock reports nearly halving from 15 down to 7 stations. P98 also improved sharply, from 22 down to 11 stations. Supply seems to be catching up on premium grades.

SA Metro Petrol Price Forecast: Next Three Days

The U91 metro forecast points to a gentle upward drift. From the current 179.0 c/L, prices are expected to reach 179.9 c/L on Monday, 180.1 c/L on Tuesday, and 180.6 c/L by Wednesday (65% confidence). No dramatic swing is expected, but the trend is slowly creeping upward.

How to Save on Fuel in SA This Week

Last Monday, 4 May, was the cheapest day to fill up in metro SA, with U91 averaging just 176.6 c/L. Prices climbed steadily through the week from there.

For the week ahead, if you're on petrol, filling up sooner rather than later makes sense given the forecast drift upward. If you drive diesel, you've caught the market at a good point. Metro diesel at 238.2 c/L is down nearly 5c on last week, and rural SA dropped almost 9.5c, so top up now while the slide holds.

E10 remains the most wallet-friendly option in metro SA at 172.8 c/L, about 6.2c cheaper than U91 if your car supports it. Check your owner's manual if you're not sure.

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