The company estimated that passenger traffic in Spain has returned to the 2019 level in October and it said it sees the positive trend continuing as airlines offer 5.3% more seats this winter than in 2019-2020.

Aena now expects overall traffic in 2022 will be higher than its prior forecast of 85% of 2019 traffic volume.

Even though 60% more passengers went through its airports in the third quarter, Aena's overall revenues rose a modest 33%, the company said. The company's commercial revenues, its share of business made from airport shops fell 13% due to COVID-19 regulations to protect shop owners.

As a result third-quarter net profit of 335 million euros ($335.80 million) was 11% lower than expected, RBC's analyst Stephanie D'Ath said on Wednesday. Shares traded 0.1% lower in late morning.

Additionally Aena's operating expenses jumped in the first nine months from the same period a year ago, mainly driven by its electricity bills, which rose three-fold.

Britain's biggest airport, Heathrow, warned earlier it was unlikely to return to pre-pandemic demand for several years, except at peak times, due the global economic crisis that follows the impact of COVID-19.

($1 = 0.9976 euros)

(Reporting by Inti Landauro and Corina Pons, Editing by Catherine Macdonald and Louise Heavens)

By Inti Landauro and Corina Pons