Retail fuel prices rose for the first time in six weeks on 3 March, and then again over 9-10 March, with petrol up 8 cents per litre and diesel 5 cents in total since January. The increases reflect steadily rising international commodity prices since the last price change in mid-January, which were initially absorbed by oil companies until the importer margin (retail price less costs) was gradually eroded to the point that a price increase was not unexpected to restore margins to the upper end of the range.

Since the last retail price drop on 19 January, crude oil prices have risen 5%, while refined petrol prices are up 6.5% and diesel up 5.5%, and at the same time the kiwi$ has fallen from US$0.74 US cents to US$0.70. The combined effect means the landed cost of petrol, in NZ dollars, has risen about 9 cents per litre, hence the pump price rises.

Commodity prices appear to be increasing with demand slowly returning as the global economy improves, putting pressure on refinery output and supplies, which were cut back after demand fell significantly following the global economic crisis in the latter half of 2008.

AA PetrolWatch notes that the differential between 91 and 95 octane petrol is now 7-8 cents per litre depending on brand. Many motorists will be unaware of this, as service stations now tend to only advertise the price of 91 octane and diesel. Traditionally, the price gap was just 5 cents but it has been slowly rising due to increasing costs for premium fuel during last year (although lately the cost has fallen back). 98 octane petrol, where available, sells for 15c more than 91 octane.