Use Loyalty Miles
One of the best ways to score a free flight upgrade is to use miles from your airline's frequent flyer program. Most major airlines allow members to redeem accrued miles for cabin upgrades on flights. The number of miles generally required varies depending on the airline, length of the flight, and route demand, but starts at around 15,000 miles for a one-way domestic upgrade. International flights may require up to 100,000 miles or more for a roundtrip upgrade.
It's wise to save your hard-earned miles specifically for upgrades instead of splurging on tickets or other benefits. Keep a stash reserved in your account as your “upgrade fund.”
Check how many miles your desired routes or cabins require so you can plan your savings accordingly. Confirm upgrade award availability a few days before booking flights.
Elevate Your Status Level on Your Preferred Airline
Gaining elite status level in an airline's loyalty program brings a wide range of perks, including complimentary upgrades. Depending on the tier, elites can earn from a few to dozens of system-wide upgrade certificates per year to confirm moves to first or business class. For example, American's AAdvantage Executive Platinum members (earned by flying 100,000 miles or 120 flight segments annually) get eight system-wide upgrade certificates each year.
Prioritize achieving and maintaining elite status on your preferred airline, even as a part-time frequent flyer, to enjoy the upgrade benefits. Check the airline's requirements for tier qualification and consider getting an airline credit card which earns qualifying miles through spending bonuses. The higher elite level you reach, the more upgrade perks will come your way.
Check-in as Early as Possible
Airlines often allocate seat upgrades in advance of the flight—sometimes weeks or days ahead. To get your name high on the upgrade waitlist, check-in online as early as the airline app or website allows—usually 24 hours pre-departure. This gives you priority over passengers who check in later.
Alternatively, you can request an upgrade as soon as you book your ticket, though you’ll have to waitlist and keep your fingers crossed. Calling the airline after ticketing and politely asking about upgrades can also work in some cases. The earlier you check-in and inquire, the more likely you'll land that bump up.
Dress “Business Casual” (Really)
While airlines claim appearance doesn't actually influence cabin upgrade decisions, looking “tidy” and professional can potentially make you “presentable enough” to be moved up to business or first class. Avoid the torn jeans look, graphic tees and casual athletic wear. Instead, dress like you “belong” in a premium cabin. For men, wear unwrinkled pants or chinos with a collared shirt. For women, avoid sweatpants and opt for a blouse or sweater.
Be Flexible About Seat Selection
When hoping for a free upgrade, try not to get too attached to a particular seat assignment or location in your current cabin class. Being flexible allows the airline to more easily shuffle you into an available upgrade seat. If you select a specific non-upgrade economy seat, it limits the airline's ability to move you up.
Travel During Off-Peak Times
A flight's upgrade availability depends heavily on the load factor—how many passengers are booked and occupying seats. During busy holiday travel times when planes are packed, upgrades are nearly impossible. Shoot for traveling during less crowded weekday or off-season flights to significantly boost your chances. Being flexible and willing to travel at less popular times can definitely impact your upgrade success.