(FOX) - Air-Tran is adding a charge for overweight customers.
The airline will begin requiring passengers to purchase two seats if company employees deem them to be "customers of size."
Air-Tran will begin enforcing the policy March 1.
Southwest Airlines completed its takeover of Air-Tran in May. Its website says it has followed the "customers of size" policy for thirty years.
Southwest's website also says the airline estimates the policy likely affects "far less" than one-half of one percent of its customers.