- AirTran routinely sells upgrades at the gate, on a space available basis, for $40 to $140 each way. AirTran normally limits those upgrades to travelers with full-fare coach tickets, but it's currently selling upgrades from any coach fares as a "promotion."
- Although, as far as I know, no official tariffs mention them, travelers report that some legacy lines are selling space-available upgrades at the gate: some to travelers on any sorts of tickets, others just to travelers on expensive base tickets. Since this practice doesn't seem to be documented anywhere, I guess you just have to see what happens at the gate.
Mileage and coupon upgrades
For most travelers on the big legacy lines, the route to the front cabin runs through the frequent flyer program. And, for the most part, how easily you can do that depends on (1) how high you are in the program, and (2) how much you pay for the ticket you're trying to upgrade.
- The one way you can assure yourself a confirmed seat in the front cabin is to use miles, either for a "free" seat or to upgrade a coach or economy ticket. When I last looked, going for the "free" seat is the better use of your miles. And although this system provides a confirmed seat, seats for either upgrades or "free" awards are extremely scarce—virtually nonexistent on some lines, especially for first class to Hawaii and business class to Europe. As with most perks, anecdotal evidence indicates that super-elite travelers find seats easier to get than ordinary frequent flyers.
- Most of the legacy lines also sell upgrade coupons or certificates, generally denominated in multiples of 500 miles, for domestic trips. Give the airline as many as required for your trip. The type of coach ticket you can upgrade with coupons—and how soon you can confirm a seat—depend on your frequent flyer status. In general, if you're not at least one elite level up the scale, you can't use coupons with anything but the most expensive coach tickets. In my experience, low-ranking frequent flyers on cheap tickets must play rostrum roulette at the gate, with realistically very little chance of using their certificates.
- Legacy lines issue a variety of other upgrade certificates, mostly either through corporate travel programs or to high-ranking frequent flyers. If you're eligible, you already know about them; if not, you'll never see them.
'Free' upgrades
On domestic flights, probably no more than two out of 10 travelers actually buy first-class tickets. Instead, the legacy lines fill their small (and shrinking) first-class cabins by upgrading travelers on coach tickets, free, without requiring cash payment or coupons.
- Although most lines don't publish their formulas, it's pretty clear that the priority for free standby upgrades depends on a combination of frequent flyer status and the price of the coach ticket. Super-elite frequent flyers on full-fare coach tickets almost always get upgraded; ordinary frequent flyers on cheap tickets almost never do.
- That old bromide about "dress up and ask politely" is, at best, an urban legend. It may have worked 20 years ago, but now, any flight I've taken lately has left the gate with lots of upgrade-eligible frequent flyers consigned to the back of the plane.
- From what I hear, free upgrades are extremely scarce on overseas flights, even for super-elite flyers.
No free lunch
Clearly, upgrading generally requires some combination of cash, miles, and luck. The exact combination depends on the airline, your ticket, and your frequent flyer status. In my view, escaping the cattle car is worth the effort, but I'm sure many of you just resign yourselves to the miseries of coach.

