First class on commercial airlines is shrinking because carriers have discovered they can generate more revenue by installing larger business-class cabins rather than a handful of ultra-luxury seats.

Add Yahoo as a preferred source to see more of our stories on Google. Set alerts for tools like Points Path that check inventory across airlines, making it easier to spot available first-class seats.

Flying in first class may sound like a once-in-a-lifetime luxury, but according to upgrade expert Jennifer Yellin of Points Path, it’s more attainable than many travelers realize. With the right mix ...