A one-look answer for regular unleaded in Australia’s five largest cities: where the ACCC buying tip sits in the petrol price cycle, and what that means for filling up. This is a guide, not a forecast of cents or of the cheap day.
Buying tips last updated (3 days ago) — ACCC weekday label “Friday”, transcribed 2026-09-26. ACCC petrol price cycles.
Phase: climbing
Prices have increased. Motorists looking to buy petrol can shop around for lower priced retailers.
Prices have risen. Shop around — do not wait for a trough day this tip does not name.
ACCC buying tip, last updated · ACCC petrol price cycles in the 5 largest cities. Around 5 weeks on average in 2025 (ACCC).
Phase: climbing
Prices have increased. If motorists shop around, they may find some retailers who have not yet increased prices.
Prices have risen. Shop around — do not wait for a trough day this tip does not name.
ACCC buying tip, last updated · ACCC petrol price cycles in the 5 largest cities. Around 6 weeks on average in 2025 (ACCC).
Phase: climbing
Prices have increased. Motorists looking to buy petrol can shop around for lower priced retailers.
Prices have risen. Shop around — do not wait for a trough day this tip does not name.
ACCC buying tip, last updated · ACCC petrol price cycles in the 5 largest cities. Around 6 and a half weeks on average in 2025 (ACCC).
Phase: climbing
Prices have increased. Motorists looking to buy petrol can shop around for lower priced retailers.
Prices have risen. Shop around — do not wait for a trough day this tip does not name.
ACCC buying tip, last updated · ACCC petrol price cycles in the 5 largest cities. Around 2 and a half weeks on average in 2025 (ACCC).
Phase: falling
Prices are decreasing and may decrease further. Motorists looking to buy petrol can shop around for the lowest prices.
Prices are coming down and may fall further. Shop around for the lowest pump.
ACCC buying tip, last updated · ACCC petrol price cycles in the 5 largest cities. Around 1 week on average in 2025 (ACCC).
Retail diesel (and automotive LPG) prices do not move in petrol price cycles. The ACCC does not publish diesel buying tips or a diesel phase.
The five-city diesel average on 23 September 2026 was $2.87/L (286.8 cpl). That is a weekly average from the ACCC monitoring report, not a phase label. Shop around on a fuel-price app the same way you would for petrol; do not wait for a diesel cycle that does not exist.
| City | Average | Phase |
|---|---|---|
| Sydney | 284.7 cpl | None — diesel does not cycle |
| Melbourne | 288.5 cpl | None — diesel does not cycle |
| Brisbane | 289.8 cpl | None — diesel does not cycle |
| Adelaide | 289.6 cpl | None — diesel does not cycle |
| Perth | 281.3 cpl | None — diesel does not cycle |
| 5 largest cities | 286.8 cpl | None |
The ACCC publishes buying tips for regular unleaded in Sydney, Melbourne, Brisbane, Adelaide and Perth at least Monday, Wednesday and Friday around midday. We transcribe those tips and map the language to one of five phases: climbing, near peak, falling, near low, or plateau. The phase is a CalcFuel label for ACCC wording. It is not a prediction of the next peak, the next trough, or a price in cents per litre.
Cycles vary from cycle to cycle and by suburb. ACCC says to use the tips as a guide only. When a tip says prices have increased, or that cycles are disrupted, we use climbing or plateau — we do not invent a cheap day. Canberra, Hobart, Darwin and most regional towns do not have petrol price cycles, so they are not on this page.
Since late February 2026 the ACCC has noted that petrol price cycles have mostly not occurred in Sydney, Melbourne, Brisbane and Adelaide. That is why a city can sit in climbing without a named trough. Perth still often moves on a shorter weekly pattern; the live tip, not the 2025 average length, is what the card follows.
Across all fuels, ACCC finds that shopping around with a state price app still saves money: FuelCheck in NSW, FuelWatch in WA, and the other apps listed on the ACCC cycle page. A city average is not the price on your corner.
docs/accc-cycle-tips-refresh.md. A build check fails when the oldest tip is 7 days old or older (override with CYCLE_TIPS_ALLOW_STALE=1). There is no auto-scrape.