Cell towers in Chamonix-Mont-Blanc

The widest declared gap between neighbouring supports is about 2.8 km, to the north-east of the centre. 1 support is declared underground, in a gallery or a tunnel. For questions about exposure, see the exposure guide.

Declared supports include 1 underground or tunnel site, 1 church or religious building and 1 water tower, with buildings making up most of the remainder.

Antennas are listed at Les Nants, Le Montenvers, Argentière Est - Eglise, Les Bois Prins Moussoux, Aiguilles des Grands Montets and Tunnel Mt-Blanc.

ANFR has approved 3 new sites that are not live yet, plus additions on 7 existing masts. New: Bouygues Telecom (3G, 4G and 5G) at Charamillon, Free Mobile (4G and 5G) at Aiguille du Midi and SFR (2G, 3G and 4G) at Plan des Aiguilles 100. 16 Bouygues Telecom 5G transmitters are listed as technically operational — installed, but not yet declared commercially in service.

The tallest structure is a 42 m pylon at Les Bois Prins Moussoux. The median is 21 m, slightly below the Haute-Savoie median of 26 m.

4 masts belong to the commune itself and 3 to Totem; the rest sit mainly on private buildings.

Systems from 1997 are still on the register. Free Mobile opened 5G here in January 2021; Orange followed in July 2021, SFR followed in March 2022. 2017 was the busiest year, with 71 new systems, most of them 4G.

On 3.5 GHz, the fastest 5G band: Bouygues Telecom on 8 of its 12 masts, SFR on 8 of its 14 masts, Orange on 6 of its 16 masts and Free Mobile on 4 of its 8 masts. 5G is on 52% of masts here, against 80% across Haute-Savoie towns with five or more masts.

3 masts carry all four networks; 10 supports carry only Orange.

Among the 33 Haute-Savoie towns with at least five masts, Chamonix-Mont-Blanc ranks 2nd by mast count. With 27 masts for 8,705 residents, or 31 per 10,000, it has more masts per inhabitant than the median for those towns (10).

Nearby, Saint-Gervais-les-Bains (12 km to the west) has only 10 masts.

Figures above cover installations declared to ANFR as in service or technically operational, as of October 2026; approved projects are not counted.