As international crude oil prices respond to the unfolding events in the Middle East, the ACCC is examining international and domestic fuel price movements and market behaviour.
"The international price of refined petrol is a key driver of Australian retail petrol prices. While these international costs are largely outside the control of local petrol retailers, we remind retailers that making false or misleading statements to consumers about the reasons of price increases would be in breach of the Australian Consumer Law," Commissioner Anna Brakey said.
"The ACCC will not hesitate to take action if representations and market behaviour by a petrol company contravene competition and consumer laws," Ms Brakey said. "We have written to major fuel companies to set out our expectations about domestic fuel pricing as these international events unfold."
"At this time, as at any time, we encourage motorists to use fuel price apps and websites to shop around to find the lowest prices."
Petrol prices were slightly higher in the December quarter 2025
Petrol prices over calendar year 2025 were lower than in 2024, but rose slightly in the December quarter 2025 compared with the previous quarter, the latest ACCC petrol monitoring report found.
In the December quarter 2025, average retail petrol prices across the five largest cities (Sydney, Melbourne, Brisbane, Adelaide and Perth) were 180.4 cents per litre (cpl), 1.6 cpl higher compared with the previous quarter, the report found.
The following figure shows the movements in average retail petrol prices in 2024 and 2025 across the five largest cities. It also shows that average retail prices fluctuated in the December quarter as petrol price cycles in the largest cities moved lower and higher.
Seven-day rolling average retail petrol prices across the five largest cities in nominal terms
Source: ACCC calculations based on data from Informed Sources.
Notes: The grey shaded area in the figure represents the December quarter 2025.
A 7-day rolling average price is the average of the current day's price and prices on the 6 previous days.
Quarterly average retail prices increased in each of the five largest cities, except in Perth, where prices were the same as the previous quarter.
"While average prices were higher in the largest cities in the December quarter, they were overall lower in calendar year 2025 than in 2024," Ms Brakey said.
In 2025, annual average retail petrol prices across the five largest cities were 179.3 cpl, 8.7 cpl lower compared with 2024.
In Canberra, Hobart and Darwin, quarterly average retail petrol prices were also higher than the previous quarter.
Across over 190 regional locations that the ACCC monitors, average retail petrol prices (in aggregate) were 180.6 cpl, an increase of 0.7 cpl from the previous quarter.
Retail and wholesale other costs and margins were the main contributors to higher quarterly average prices
Higher quarterly average prices largely reflected higher retail costs and margins (gross indicative retail differences), as well as certain wholesale costs and margins. Gross indicative retail differences are a broad indicator of gross retail margins and include both retail operating costs and retail profits.
Average gross indicative retail differences across the five largest cities (in aggregate) were 17.9 cpl in the December quarter 2025, 1.5 cpl higher than the previous quarter. In calendar year 2025, annual average gross indicative retail differences were 16.3 cpl, 0.2 cpl higher than the 10-year real terms average.
Crude oil and international refined petrol prices were lower on average in the quarter, and fluctuated in early 2026
Crude oil prices trended downward during the December quarter 2025 despite geopolitical tensions as global inventories increased to their highest level in nearly four years. International prices for refined petrol (Mogas 95) prices were relatively more stable and were also lower on average than in the previous quarter.
In early January 2026, crude oil prices spiked, influenced by geopolitical developments in Venezuela and Iran, before easing by mid-January. The movements in January had minimal influence on Mogas 95 prices movements.
Over the last week, international crude oil and Mogas 95 prices have increased sharply, influenced by the Middle East conflict.
Diesel prices increased in all capital cities
In the December quarter 2025, average retail diesel prices increased in all capital cities. Across the five largest cities, quarterly average retail diesel prices were 185.9 cpl, an increase of 4.1 cpl from the previous quarter.
Annual average retail diesel prices in calendar year 2025 across the five largest cities, were 4.9 cpl lower compared with 2024.
More recently, over the last week we have seen the international benchmark price for refined diesel increase significantly.
New electric vehicle sales reached a record high in December 2025
Almost 17 per cent of all new vehicle sales in December 2025 were new electric vehicles, representing the highest monthly electric vehicle market share ever recorded in Australia.
In calendar year 2025, electric vehicle sales rose by 38 per cent compared with 2024 and represented just over 13 per cent of all new vehicle sales.
Note
Singapore Mogas 95 Unleaded (Mogas 95) is the relevant international benchmark for the wholesale price of petrol in Australia. Singapore Gasoil with 10 parts per million sulphur content (Gasoil 10 ppm) is the international benchmark for the wholesale price of diesel.
Gross indicative retail differences represent the difference between average retail petrol prices and indicative wholesale prices.
'Petrol' means regular unleaded petrol unless otherwise specified.
Price changes are reported in nominal terms unless otherwise specified.
Background
On 10 December 2025, the Treasurer issued a new Ministerial Direction to the ACCC to monitor the prices, costs and profits relating to the supply of petroleum products in the petroleum industry in Australia, for a further five years commencing on 1 January 2026. The ACCC is required to give the Treasurer a report on the monitoring at least once every quarter.
Link to the new direction.
In February 2026, The Federal Court ordered Mobil Oil Australia to pay $16 million in penalties for making false or misleading representations about the fuel sold at nine petrol stations in north and central Queensland, in breach of the Australian Consumer Law.
