Reply #4: Typically... [View All]

though some airlines now offer their lowest rate to "cash and carry" customers the day of the flight (to unload unsold seats, as unsold seats cost them money.) It's usually weird destinations, it typically doesn't apply to any flight with a layover, connection, or stopover. Unless you're desperate for a low rate and are willing to fore-go your trip if it can't be done cheaply, I would not go this route to acquiring plane tickets because sometimes you can get hammered (paying the highest rate) if you're trying to buy tickets to a desirable destination.

Some other airlines, Southwest for example, offer an "everyday low rate" on certain routes. Typically these originate and arrive at smaller airports outside the major city. I, for example, can fly from Manchester, NH (1 hour outside Boston, 3 hours outside Hartford) to BWI (45 minutes outside of DC) for $59 (plus certain fees.) regardless when I buy the ticket, provided it's not day-of-flight.

Generally though, you get a better rate to buy early.