While the mainland frets about petrol prices smashing through the $3 mark, those living on Great Barrier Island are already forking out that amount for 91.

Following a snapshot of the nation's petrol prices yesterday, readers have been getting in touch with prices at their locals pumps.

One reader from Great Barrier Island sent through a picture of what must surely be the priciest petrol in New Zealand: 91-octane fuel selling for $3.11 a litre.

He said residents had been paying more than $3 a litre "for some time now".

Another reader quoted a price of $3.05 per litre for the Chatham Islands.

Petrol prices have climbed to new heights, with many service stations selling 91 above the previous high of $2.27, which was reached in 2013.

A previous informal survey of regional fuel prices conducted by NZME in 2015 found the most expensive fuel was on both Chatham and Great Barrier islands, selling for $2.90 a litre at the time.

Great Barrier residents have requested exemption from the Government's Regional Fuel Tax, which will pump prices up by 11.5 cents a litre from July, following concerns petrol is becoming too expensive for some islanders.

As part of Auckland Council's submission on legislation for a fuel tax, it is asking for the ability to exempt certain geographical areas from the tax, using Great Barrier as an example.

Yesterday the Herald asked NZME staffers across the country to send photos of prices at the pump in their towns and cities to see how they fared.

The unscientific survey received more than 100 responses and was enacted after fuel prices hit $2.30 at some stations yesterday.

Pundits said increasing prices for crude oil on the global market and a depreciating Kiwi dollar meant there was little to be done about prices, while others including the AA called for both petrol companies and the Government to reduce prices.