On Tuesday, United Airlines announced that its prices on its flights to Philadelphia would increase by $1.75 to $100.
For United, that is a significant increase.
The airline announced the increase in late May after the Federal Aviation Administration revised its pricing guidelines.
United Airlines, however, did not disclose how much it would have to raise prices for tickets between its Philadelphia and Washington-Dulles hubs.
The Philadelphia-Washington-Dully hubs are two of the busiest in the country and serve more than 2.5 million people a year.
United announced last month that it would be increasing prices on United’s tickets between the hubs by $2 for those flying from Philadelphia and $6 for those from Washington-DC.
United is the third major U.S. airline to increase prices.
On Tuesday’s flight from Chicago to Chicago, United raised prices by $4 to $140.
And last week, United increased the cost of a Chicago-San Francisco-San Jose flight from $120 to $180, and the cost for the same flight from New York to San Francisco by $50 to $200.
This article originally appeared at Business Insider.