United is offering one-year subscriptions for Economy Plus seats or pre-paid checked baggage.
The Economy Plus subscription starts at $499 and the checked-baggage subscriptions start at $349.
Customers can select their region and the number of travelers on their Economy Plus subscription. For the checked-baggage subscription, customers can choose up to two bags, the number of travelers and preferred geographic region.
Subscriptions are available on United.com or through United reservations.
When customers buy a ticket, United recognizes their eligibility for Economy Plus seating and offers them that seat assignment.
United said that it is is the only U.S. carrier to offer an annual subscription for economy seats with extra legroom and checked baggage.
Additionally, customers may now use loyalty miles to purchase an annual United Club membership. One-year membership starts at $500 or 65,000 miles, with discounts for Premier members.
An initiation fee of $50 or 7,000 miles applies for all new United Club memberships.
Follow Kate Rice on Twitter @krtravelweekly.