One electronic ticket will now link flight itineraries for passengers flying on both American and United airlines.

The recent agreement, called ticket interlining, gives passengers and planners more flexibility to create flight schedules with e-tickets, especially those who need to rebook flights and want to switch air carriers. Previously, e-tickets had to be converted to paper in order to accomplish the same goal. American and United have linked their databases, allowing e-ticketed passengers similar freedom.

United also interlines e-tickets with its Star Alliance partners, Air Canada, Continental Airlines, and Northwest Airlines. Continental interlines with Northwest and America West Airlines.