Line 5 + Express on the route: Airport - Thônex Vallard (via the following stops: Palexpo, Grand-Saconnex, Nations, Gare Cornavin, Terrassière, Muséum, Rieu, P+R Sous-Moulin), with 4 frequencies in the morning and in the evening both ways.
Line V + on the route: Airport - Montfleury (via the following stops: Fret, Tunnel Routier, Valavran, Vieux-Valavran, Genthod-Village, La Pralay, Les Fayards, Entrée-Versoix, Versoix-Bourg, Versoix-Gare, Versoix-Argand, Pont-Céard, Port Choiseul) with 2 frequencies in the morning from Montfleury to the airport and two frequencies in the evening from the airport to Montfleury.
Detailed schedules: www.tpg.ch