The national carrier hedged about 3.12 million barrels, or 70 per cent of estimated fuel consumption, in the first six months of calendar 2018, which it projected would generate an unrealised gain of $30.7 million, according to its February 14 hedging position.
For the final six months of 2018, the airline hedged 1.69 million barrels, or 35 per cent of estimated consumption, likely to generate an unrealised gain of $88,000.
Forysth Barr head of research Andy Bowley said international airlines can't always fully recoup higher costs due to the competitive nature of the industry, with a greater number of carriers competing more aggressively and through a wider array of channels.
That contrasts with the domestic market, where Air New Zealand faces just one competitor of scale in Qantas Airways subsidiary Jetstar.
Government data show consumer prices for domestic airfares rose 3.9 per cent in the March quarter from a year earlier, whereas prices for international fares fell 6.6 per cent.
Over the same period, input prices paid by rail, water, air and other transport producers rose 2.4 per cent.
Bowley said fuel pressures will affect the sector in the second half of 2018, but Air New Zealand's hedging offers some protection.
"I think the cost pressures are going to be at a similar level in the second half, that doesn't mean that the fuel price on average isn't the same, it's a reflection of what the cost pressures in the prior year were as well."
The airline's fuel bill jumped 21 per cent to $470m in the six months ended December 31 and was a major contributor to Air NZ's 7.5 per cent increase in operating costs to $2.03 billion.
The shares recently traded at $3.39, having gained 6 per cent so far this year and outpacing a 2.6 per cent increase on the S&P/NZX 50 index over the same period.
The stock is rated an average 'hold' based on six analyst recommendations compiled by Reuters, with a median target price of $3.14.