Yes, you can upgrade from United Economy to United Polaris® business class using several methods. The most straightforward way is a Paid Upgrade, which can be purchased via the United app or website under "My Trips." For frequent flyers, MileagePlus Upgrade Awards allow you to use a combination of miles and a cash co-pay (depending on the original fare class). If you have Premier Platinum or 1K status, you can use PlusPoints to request a seat in business class, with long-haul upgrades typically costing 40 to 80 points. Additionally, Premier members are eligible for Complimentary Premier Upgrades on select short-haul domestic and regional flights, which are processed automatically starting five days before departure. Always check the "Upgrade Standby List" in the app on the day of travel for real-time status updates.