Queensland's $1 a litre petrol bowser bonanza

One service station chain has ignited southeast Queensland's petrol price war by dropping fuel to below $1 per litre - the cheapest in six years.

The plummeting prices come as an RACQ report shows 2014 was the most expensive year on record to fill up in Queensland.

Costco at North Lakes yesterday was selling unleaded fuel for 99.7¢ a litre, the first time the price at the bowser had dipped below a dollar since early 2009.

In Brisbane, the ULP average was $1.09 per litre, the lowest in more than five years.

Make the most of the prices now because they can't last forever

Prices have been gradually forced down by a global oil glut caused by steady supplies, weakened economies and a drop in demand, particularly in Europe and Asia.

But motorists have been warned the pump prices could flatline soon and eventually rise once the global market stabilises.

"We're just saying make the most of the prices now because they can't last forever," RACQ spokeswoman Renee Smith said.

"The worst thing you can do is wait until you're on empty to fill up. If you can get the lowest price, take advantage of it while you can." Long queues of motorists waited at Costco outlets at North Lakes and Mango Hill, where unleaded fuel sold for $1.02 per litre yesterday morning.

The American retail giant only offers discounts to its membership, but Ms Smith said its price drop would put pressure on surrounding petrol stations.

Brisbane's ULP average was $1.50 per litre, peaking at $1.65 per litre last January

Costco opened its stores in the Brisbane area last year to take on other discount fuel retailers such as Coles and Woolworths.

The company's Australian chief executive, Patrick Noone, said the success of these stores paved the way for expansion.

"We'd like to build a couple more stores in Brisbane in the south or southwest," he said.

"People are very happy. When you're working with very slim margins, you can offer these prices." Ms Smith said although southeast Queensland was enjoying the benefits at the bowser, regional motorists were still paying too much.

Cities such as Cairns, Townsville and Rockhampton were paying about 5¢ a litre more.

But that is still a stark contrast to last year's record high prices. RACQ's annual fuel price report shows Brisbane's ULP average was $1.50 per litre, peaking at $1.65 per litre last January.

The average mark-up at city petrol stations was 10.2 per cent. Weipa motorists paid the highest price in the state at the pump, forking out $1.78 per litre for most of the year.