The "throw away ticket" approach to saving money on air travel amounts to booking a discounted round-trip ticket but only using one part of it, rather than booking a more expensive one-way fare.
The throwaway ticket trick is similar to the back-to-back ticketing plan. It allows travelers to save money by buying a less expensive round-trip ticket and only using one leg of it.
How to Save Money Using the Throw Away Ticket Trick
Like other ticketing ploys, the "throw away ticket" approach isn't something that the airlines like. The ploy is rather simple: a business traveler simply purchases a discounted round-trip ticket instead of the more expensive, one-way ticket.
An example of "throwaway ticketing" ticketing trick would be a business traveler who wants to fly from city A to city B (say New York to Los Angeles). But when checking airfares, the traveler finds out that a round-trip flight from New York to Los Angeles is cheaper than a one-way ticket from New York to Los Angeles. For example, the round trip fair might be $450, while the single, one way fair might be $700.
Business travelers thinking about using the "throw-away ticket" approach would need to make sure they're actually using the first leg of the round trip ticket, not the second leg. That's because airlines will (might) cancel the return flight ticket if the initial ticket wasn't used.