Fare classes are the airline industry's secret language, and understanding them gives you a huge advantage - especially when you're booking business travel without a traditional TMC. These letter codes determine everything from upgrade eligibility to how many miles you earn.

In economy, "Y" is your holy grail - full-fare economy that's completely flexible and upgrade-eligible. "B" and "M" are the sweet spot for business bookings - mid-range fares that usually qualify for upgrades and earn decent miles.

Stay away from "N," "O," and "L" fares if you care about status - they're basic economy in disguise with terrible earning rates and no upgrade potential.

Business class has its own hierarchy. "J" is full-fare business (expensive but maximum benefits), while "C" and "D" are discounted but still solid. "P" fares can be tricky - on American, they're cheap business class that sometimes don't qualify for systemwide upgrades. I've been burned by this booking last-minute international trips.

What I appreciate about Otto The Agent is how it demystifies this alphabet soup without requiring a TMC contract. If you ask Otto about fare classes, it shows the fare class and immediately tells you what it means: "Upgrade eligible, full mileage earning" or "Restricted fare, limited benefits." No more guessing whether that cheap business fare will work with your Global Upgrade certificates.

For independent business travelers who don't want to be tied to a TMC, having this intelligence at your fingertips is game-changing. You get the sophisticated fare knowledge without the overhead and restrictions of traditional corporate travel management.