United Airlines will begin selling basic fares for domestic first class and short-haul international business class. The move comes after United’s introduction of unbundled basic fares for premium economy and the Polaris international business class.

United First Base fares will be lower than United First Standard and United First Flexible, but with fewer add-ons. Customers will pay extra to select a seat and get just one free checked bag. They won’t be allowed to make itinerary changes or receive refunds or flight credits for voluntary cancellations.

United Business is the name the airline gives to fares purchased for the first-class cabin on short-haul international flights, including to Canada and Latin America. Standard and Flexible United Business fares offer similar perks to domestic first class, except that they come with United Club access.

The new United Business Base fare does not include club access. And as with First Base ticketholders, customers will have to pay for a seat assignment, will receive just one free checked bag and won’t be allowed to make flight changes or be eligible for refunds or flight credits. United markets the Base fares as a way to give customers the choice to select the travel experience and price point that best meet their needs.