Iran war: Petrol stations raising fuel prices but not ‘over-reacting’, says ComCom
Thursday, 19 March 2026
Retail prices for fuel are rising ‒ and set to rise more still after today’s big attacks on oil infrastructure across the Middle East ‒ but retailers do not appear to be increasing prices faster than their costs.
That’s according to the Commerce Commission, which is publishing regular fuel price monitoring reports in response to the conflict in the Middle East and the impact on global fuel prices.
Today’s missive showed national retail prices have continued to climb by around 55c per litre for petrol and 90c per litre for diesel since the start of the Iran conflict.
That is a 21% increase in Regular 91 petrol since February 28, and a 48% increase in retail diesel.
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But costs to the companies importing in the fuel have risen faster ‒ a 61% change for petrol and 107% for diesel.
The reason for the disparity between these two sets of figures is that exporting today would be particularly expensive given what has happened this morning in the Middle East. The retail figure, on the other hand, uses petrol bought more cheaply a time ago, and also distributed more cheaply, before any very recent inflation is taken into account.
The two sets of figures will likely become closer as time goes on.
In any case, at the pump, “overall, the steady pace of these increases suggests that at a national level, fuel retailers are not overreacting to spikes in costs”, the commission said.
The commission sent a strongly worded letter to fuel companies on March 12, warning it did “not want to see fuel companies using the situation in the Middle East as an opportunity to increase prices by more than their costs are increasing”.
It also expected to see costs decrease once the cost of importing fuel fell, it added.
The reports it has subsequently released are based on a comparison of the change in Brent crude and refined products (petrol and diesel) cost with the change in average retail prices for each of Regular 91, Premium 95 and Diesel.
The calculations take into account things like the benchmark cost of buying refined fuel from Singapore, shipping rates and the freight multiplier, and insurance costs.
“Concerning” price behaviour would be called out publicly, commissioner Bryan Chapple said.