US Airways plans to begin the flight in March using Airbus A330s.
Right now, US Airways flies from Charlotte to London's Gatwick airport, but business travelers generally prefer Heathrow. A US Airways spokesman said the airline hasn't decided what it will do with the current Charlotte-Gatwick flight.
The new route is in addition to the Philadelphia-to-Heathrow service the airline currently offers.
Shares of the Tempe, Ariz.-based airline rose 38 cents, or 3.2 percent, to $12.45 on Tuesday. Its shares have ranged in a 52-week range of $3.96 to $14.51.