Iran war: Pump price of 91 has risen by more than the imported cost, new figures suggest
Thursday, 26 March 2026
Petrol companies may have increased the price of 91 octane petrol by more than could be justified by the rising cost of purchasing new supplies, figures released late on Thursday afternoon by the Commerce Commission suggest.
However, the competition watchdog is warning it is too soon to jump to conclusions and is not crying foul as yet.
The price of buying refined fuel on Asian markets fell back sharply on Tuesday and Wednesday, according to the Australian Institute of Petroleum.
But the retail price of petrol hasn’t dropped and the price of diesel has continued to creep up.
Read more:
Police keeping eye on fuel crisis, ready to crack down on any related crime
NZ petrol and jet fuel stocks down, diesel up, according to latest MBIE update
Price comparison service Gaspy was reporting that the average price of 91 was holding steady at just over $3.39 a litre on Thursday, while the average price of a litre of diesel had climbed to $3.31.
The Commerce Commission said in its latest update that the average price of 91 had increased by 81 cents a litre since the Middle East conflict began on February 28.
But it put the rise in its refined cost, including shipping, at 58c a litre.
The retail price of diesel has risen by $1.35 a litre since the conflict began, while it reported the increase in its refined cost at $1.25.
Z Energy, the country’s largest petrol company, has been contacted for comment.
In the case of diesel, GST could potentially account for the gap.
The Commerce Commission said when it released the first of its weekly post-war monitoring reports on March 12 that its initial analysis of petrol companies’ pricing behaviour raised no concerns.
But it has not provided a similar ‘all-clear’ alongside its more recent information releases.
Commissioner Bryan Chapple said it didn’t have enough data to suggest petrol companies had increased the price of 91 to an unreasonable level, however.
It was possible the commission’s figures were underestimating petrol companies’ purchasing costs as they involved making some assumptions, he said.
“They are not necessarily accurate for what is happening.”
Figures from the Australian Institute of Petroleum appear to tie in with the commission’s estimates, however.
It has reported the key Singaporean benchmark for 95 Octane petrol — which is more widely used in Australia — had risen from about A$115 a barrel, before the conflict, to A$190 a barrel on Wednesday, after peaking about A$245 a barrel on Monday.
That would equate to an increased purchasing cost of about 57 New Zealand cents a litre for that fuel, while the commission put the increase a little higher, at 60c.
Chapple said there might be an element of “smoothing out” taking place in petrol companies’ margins given that, earlier on in the conflict, they had not increased their prices by as much as refined costs rose.
Historically, data from the Ministry of Business, Innovation and Employment showed margins on petrol jumped around from week to week, he noted.
“You need to have a decent period of time to draw conclusions about what’s happening.”
The decision by the Iranian regime to ease restrictions on the Strait of Hormuz to “non-hostile” vessels and growing talk of a negotiated end to the conflict appear to have been the trigger for refined fuel prices coming off their highs in recent days.
But AA policy manager Terry Collins said he believed the light at the end of the tunnel for motorists was still some way off.
Collins said the AA wasn’t in the business of protecting the petrol companies, but the commission’s latest monitoring data needed to be seen in the light of them taking a haircut on their margins earlier in March.
“On diesel, they burnt the scalp,” he said.