The following airlines serve London Gatwick LGW Airport.
Airline Terminal
Adria Airways, JP North Terminal
Aer Lingus, EI South Terminal
Air Algerie, AH South Terminal
Air Baltic, BT South Terminal
Air Comet, A7 North Terminal
Air Malta, KM South Terminal
Air Southwest, WOW North Terminal
Air Transat, TS South Terminal
Atlas Blue, 8A North Terminal
Aurigny Air Services, GR South Terminal
Azerbaijan Hava Yollary, J2 South Terminal
Belavia, B2 South Terminal
BH Air, BGH South Terminal
Bmi, BD South Terminal
British Airways, BA North Terminal
Brussels Airlines, SN North Terminal
Bulgaria Air, FB South Terminal
Cimber Air, QI South Terminal
Clickair, AIS North Terminal
Croatia Airlines, OU South Terminal
Delta Air Lines, DL North Terminal
EasyJet, U2 North Terminal
Emirates, EK North Terminal
Estonian Air, OV South Terminal
FlyBE, BE South Terminal
Flyglobespan, Y2 South Terminal
Ghana Airways, GH South Terminal
KD Avia, KD South Terminal
Kibris Turk Hava Yollari, YK North Terminal
Malev-Hungarian Airlines, MA North Terminal
Meridiana, IG South Terminal
Mexicana, MX South Terminal
Monarch Airlines, ZB South Terminal
Northwest Airlines, NW North Terminal
Norwegian Air Shuttle, DY South Terminal
Olympic Airlines, OA South Terminal
Pakistan International Airlines, PK South Terminal
Qatar Airways, QR North Terminal
Ryanair, FR South Terminal
SAS, SK South Terminal
TAP-Air Portugal, TP South Terminal
Tarom, RO North Terminal
Thomas Cook Airlines UK, TCX South Terminal
Thomsonfly, TOM North Terminal
Ukraine International, PS South Terminal
US Airways, US South Terminal
Virgin Atlantic Airways, VS South Terminal

More details on airlines from the London Gatwick Airport website.