UPDATE 1-Budget airline easyJet lifts profit outlook after strong quarter

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LONDON, July 20 (Reuters) - British budget airline easyJet raised its profit outlook on Thursday after it filled more seats on its planes while keeping a tight grip on costs during the third quarter.

The airline, which is looking for a replacement for CEO Carolyn McCall who is set to join broadcaster ITV next year, said that profit before tax would be in the range of 380 million to 420 million pounds ($495 million-$547 million).

A company-supplied analyst consensus had estimated profit before tax to come in at 380 million pounds.

McCall said competition in the sector would mean prices remain under pressure, but the airline kept its cost per seat guidance for the year.

"Although we expect capacity to continue to put pressure on yields, our progress this year has enabled us to upgrade this year's PBT (profit before tax) forecast and demonstrates that after a difficult 18 months of external challenges easyJet once again has positive momentum," McCall said.

The airline also said that its European subsidiary would fly its first flight on Thursday, as it had been awarded an Air Operators Certificate (AOC) in Austria.

The approval comes less than a week after it said it would establish a new airline headquartered in Vienna to protect its flying rights in the European Union once Britain leaves the bloc. ($1 = 0.7679 pounds) (Reporting by Alistair Smout; editing by Kate Holton and Victoria Bryan)