United Airlines
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Star Alliance, Condor, Air Transat and WestJet low $160-$250 one way July fares Vancouver to London/Europe

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AA/DL/UA Chicago to Paris $499, Amsterdam $466, London $534, Moscow $481

AA/DL/UA Seattle to Germany and UK $600s October dates

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AA/DL/UA Boston fares $499 Brussels, BHX/FRA/MAN/ZRH $500s

Summer fare American $80 Dallas–Orlando round trip, $97 United

Summer fares AA/UA Phoenix–Denver $35 each way July-Sep

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UA/DL/AA/FI Washington IAD $443 to Paris and 6 other cities in $500s

Fare War United $608 DFW/PHL/PHX to Hong Kong

United LAX/SFO to New Delhi, India $703 Sep-Nov; LAX-Mumbai $776

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Significantly lower United Airlines ticket prices with OTA sites. How do they do it?