There is a significant price difference between Basic Economy and Main Cabin. In United Airlines’ Basic Economy, the airline released some restrictions, including seat selection, cancellation, change, refund, and more that must follow. Talking about the Main Cabin is a little more expensive than Basic Economy and allows you to travel freely. In United Airlines’ Main Cabin, you can select the seats of your choice even after completing the booking process. If you cancel your flight, you can claim a refund.