When looking at timetables be aware that they're in French so: L = Lundi / Monday, M = Mardi / Tuesday, Me = Mercredi / Wednesday, J = Jeudi / Thursday, V = Vendredi / Friday, S = Samedi/ Saturday & D = Dimanche / Sunday.
In-resort free shuttle services operate throughout the winter and summer seasons on 3 different circuits. Buses run every 15 to 20 minutes on the red and green lines from 07:30 to 19:00 daily, and until 23:00 on Saturdays. Shuttles between Les Deux Alpes, Bons and Mont de Lans run three times per day, the first one at 08:30 and the last at 18:00.
Remember to flag the bus. Full timetables are posted on each bus stop, take a look at the interactive town map for their location. Bikes can be taken aboard these buses, no extra charge, however, it's subject to availability as the number of bikes they can carry is limited.
Bus services will take you from Lyon and Geneva airport to Grenoble Gare Routiere, the city's train and coach station. These routes work during the summer and winter seasons. From Grenoble, take another bus to Les Deux Alpes - see below.
Buses bring you to Les Deux Alpes from Grenoble Gare Routiere (train/coach station). The most direct service is the Transaltitude direct bus. It's strongly advised that you book this online in advance, as it can get busy during the winter. Online pricing and bookings are typically available from mid-November. You should arrive at the bus at least 15 minutes before boarding with your tickets (printed out on paper or in electronic format on your smartphone).
Les Deux Alpes is connected to neighbouring ski resorts and towns via bus services. For Alpe d'Huez, take line 3030 to Bourg d'Oisans and then line 3020. There is also a daily bus from Grenoble to Bourg d'Oisans (L3000), from where you can pick up either of the connecting buses to Alpe d'Huez or Les Deux Alpes. There's no need book these buses in advance, just pay the driver on arrival.
During the winter season, there is a direct shuttle bus to Alpe d'Huez on Wednesdays and Thursdays. It leaves at 08:45 and returns at around 17:30-18:00. The service costs about 12€ return and tickets can be booked from the VFD bus station in Les Deux Alpes (112 Avenue Muzelle) or the Palais des Sports in Alpe d'Huez (70 Avenue des Brandes - the desk is in the foyer immediately on the left-hand side as you walk in).
Note that these timetables may vary throughout the year and during holidays so please contact the bus companies in advance to avoid disappointment.