Cell towers in Montgeron (Essonne)

1 church or religious building and 13 buildings and 1 pylon carry the commune's antennas.

Place names on the register include La Justice, Eglise Saint Joseph, 153 Avenue de la Republique, 119bis avenue de la République, 67 Rue du Moulin de Senlis and 8 rue Mercure.

14 systems were switched on in the past 12 months. ANFR has approved one new site that is not live yet, plus additions on 3 existing masts. New: Bouygues Telecom (4G and 5G) at 78 Chem du Dessus du Luet. 10 Bouygues Telecom 5G transmitters are listed as technically operational — installed, but not yet declared commercially in service.

2016 was the busiest year, with 28 new systems, most of them 4G. Local 5G started with Bouygues Telecom in November 2020; Free Mobile followed in December 2020, SFR followed in August 2021. The oldest transmitter still listed here goes back to 1995.

13 of the 15 masts are rooftop-mounted. The tallest support is 47 m at La Justice (building). The median is 23 m, slightly below the Essonne median of 26 m.

Of the 15 masts in the commune, only one mast carries all four networks, and Bouygues Telecom is the only carrier on 5 masts.

3.5 GHz 5G is declared by Free Mobile on all 7 masts, SFR on all 5 masts, Bouygues Telecom on 4 of its 7 masts and Orange on 2 of its 4 masts.

Nearby, Vigneux-sur-Seine (2.7 km to the west) has 15 masts declared.

At 11 km² with 24,022 residents, the commune is dense enough that most antennas sit on rooftops rather than pylons. It is part of the CA Val d'Yerres Val de Seine intercommunal grouping.

Source: operator declarations to ANFR, as of October 2026. Projects that are only approved are left out of the totals.