From The Wall Street Journal…
“You have to put your cheapskate hat on,” said Tom Parsons, chief executive of BestFares.com, a discount travel site. “You just have to check the gateway cities and do the math.”
Carriers routinely offer special deals in particular cities. But they don’t let reservation systems and online ticket sellers to combine those ultracheap fares with connecting flights in a single transaction.
It doesn’t always work, and it may involve lengthy layovers and rechecking bags (which can get expensive these days). You also run the risk of your first flight being delayed and missing the separately booked connection. But sometimes the inconveniences are minor and the math adds up: I’ve saved hundreds on flights to and from New Zealand this way. It’s worth checking into.