The airline raised the charge for changing flight plans within 21 days of a flight to $100 and added a fee of $75 for passengers who change plans with more than 21 days of notice, the Chicago Tribune reported Thursday.
Those who book a trip using MileagePlus award miles and then cancel and return the award-miles to their account will be assessed a charge of $200, the airline said, up from a previous fee of $150.
Prior to Wednesday, the airline did not charge any fee for changes made with more than 21 days of notice, the newspaper said.
The new charges do not apply to elite United travelers who are in the airline's "Premier" status, the airline said in a posting online.
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