The Greater Toronto Airports Authority said Tuesday lower aeronautical fees contributed to a $1.3 million net loss in the second quarter.

That compared with a $10.4 million profit the airport operator saw in the same period a year earlier.

For the three months ended June 30, the GTAA reported revenue of $273.4 million, a $4.7 million decrease from the previous year. Total operating expenses were $178 million, a $12.1 million increase year-over-year.

The GTAA, which operates Toronto Pearson International Airport, saw its passenger volume go up by 2.6 per cent in the first six months of this year, compared with 2012.

It said 17.4 million passengers travelled through Canada's largest and busiest airport.

Domestic passenger traffic jumped 5.1 per cent, while international passenger traffic dropped 2.2 per cent in the six-month period.

"For the past several years international passenger growth rates have been higher than both domestic and transborder passenger growth rates. Beginning in late 2012 there has been a reduction in the international growth rate from the high historical levels," the company said in a release.

The GTAA did not provide passenger traffic figures specifically for the second quarter.