Over the rest of the year, all aircraft in Southwest’s fleet will be retrofitted to accommodate the new seats with up to 5 inches of expanded legroom, the company said in a statement.

The most expensive bundle in Southwest's new fare program will be Choice Extra, which will also include the most add-ons as part of the base fare. Choice Extra ticketholders will get early boarding, two free checked bags and complimentary access to extra legroom seats at booking and complimentary internet.