How Low Can They Go?.

<FONT SIZE="+3"><B> How Low Can They Go?</B>

<I> Here are the basics on several of the major European low-cost carriers.</I>

<B>Debonair</B>: Sample one-way fares: London-Madrid from $76, London-Dusseldorf $60. Through the trade or direct sell. No Saturday night or round-trip requirements. Fares are sold on an instant-purchase basis and are non-refundable, although flights can be changed upon payment of an administration fee of about $30.

<B>EasyJet</B>: London Luton-Glasgow Prestwick from $45 one way, London Luton-Amsterdam $54. Direct sell only. No strings, but fares are non-transferable and non-refundable.

<B>Ryanair</B>: U.K.-Ireland fares from $88 for a round trip, subject to a two-night or a Saturday stay and a round-trip requirement. Through the trade or direct sell. Business travelers are offered fully flexible and fully refundable tickets for $153 round trip.

<B>Virgin Express</B>: Brussels-Copenhagen, Brussels-Geneva, Rome-Madrid all about $90 one way. Through the trade or direct sell. Ticketless. No booking restrictions. Fares are fully flexible up to 24 hours before the flight; even names and destinations can be altered. Last-minute changes incur a $25 penalty.