Buses link Chamonix directly with Geneva Airport and some also stop in Geneva itself. Transfers are generally a better option but sometimes the bus is the only way!
All these companies will drop you at the central bus station which is 2.5 km from the chalet – not very convenient. If you arrive before 7.30 you can get a bus from there to Les Praz. It’s then a 5-10 minute walk from the Flegere stop to the chalet, or you may be able to get a bus that stops at Les Vardesses.
So I would not recommend this as a way to get a large group with all their luggage to us. Taxis are very expensive in Chamonix and it will cost you more to get the last two kilometers than the first hundred! But they can be useful if one person is arriving a day later and could be collected from the station, or perhaps for a day trip to Geneva.
A transfer service can take you to Chamonix, often for a comparable price or less, and will take you directly to the door of the chalet. If you have heavy or bulky luggage like skis or a board, a transfer is almost certainly a better option.
There are three companies operating on the route:
Altibus (via Geneva)
The last buses go at around 5 pm and you need to allow plenty of time to get there as traffic can cause delays, because they go through Geneva city centre. They are extremely reliable, however, and can be very useful at off-peak times when the transfers don’t run so often. Chamonix to Geneva Airport bus times from Altibus
Easybus and Ouibus (Airport only)
Easybus runs early and late, and for a very low price. As with many offerings from this company, reviews have been mixed!
Ouibus is a low cost French service which I have heard is rather better. The site is available in English.