Rivals sometimes match its fares but more often cut back flights.

Generally, airlines match one another's fares on competing routes.

At the time, many airlines matched its fares and eliminated restrictions, but stopped short of similar fare limits, giving themselves some wiggle room.

Lufthansa, however, says it will match Singapore's lower fares.

Now, it is vowing to match Southwest's fares to the six cities from Philadelphia.

Other airlines matched Delta's fares on the same routes.

United Airlines said it would probably match Virgin Atlantic's new fares.

An airline will often match a competitor's fares on some routes, even if it means charging a lower fare for a longer flight.

And competitors that at first had not matched Eastern's lower fares, became more aggressive in their pricing.

Most other airlines have matched American's lower fares.