Z Energy's retail marketing margins have expanded as it seeks to recover refining losses.
Industry-wide figures show the average retail margin expanded from 28.2 percent in the March quarter to 29.4 percent in the June quarter.
Chief executive Mike Bennetts said his company's overall profit margins were actually lower.
He said the company runs an integrated business which means it makes a margin out of its manufacturing or processing activity at Refining New Zealand and also out of the products it sells to its eventual customers.
Mr Bennetts said there are times, such as now, when the manufacturing activity is running at a loss and so it seeks to expand the marketing margins it gets with customers.
But he said the overall margins are less than they were at prior periods, but the marketing margin alone is higher than normal.
Mr Bennetts said that is why organisations such as the Automobile Association have commented on the margins being beyond a norm that they would find acceptable.