Petrol prices fell 2 cents per litre on 17 August and again on 25 August. Diesel pump prices did not drop and remain unchanged from early July.

The reduction follows a 15% fall in crude oil costs since 6 August when petrol prices rose 2c/l, with a barrel of crude oil falling from around US$83 to US$71. However international refined petrol and diesel costs have not fallen quite as much, down 10% and 12% respectively.

While a 10% reduction in commodity prices is reasonably significant, much of this has been offset by a 3 cent drop in the Kiwi dollar since 6 August. When commodity prices rose 6% in early August, this only equated to an extra 2 cents at the pump because the exchange rate also climbed several cents.

While the drop in petrol prices is welcome, unlike petrol the oil company importer margin (retail price less costs) for diesel is above average, and AA PetrolWatch suggests diesel pump prices should also fall.

AA PetrolWatch notes that some independently-owned BP stations in Auckland and Wellington are charging fees to customers who pay by credit card. This ranges from 60c for transactions under $30, to 90c for transactions over $30. The AA advises motorists to check whether a surcharge applies, and if so consider paying by cash or eftpos instead.

The move follows a Commerce Commission agreement permitting any retailer to pass on bank fees incurred for processing credit card transactions. Previously retailers included the fees in the retail price which meant cash buyers also covered the transaction cost.