Guyancourt: François Morton's list won the town hall in 2026; Jean-Luc Mélenchon would lead here in 2027
Guyancourt (Yvelines, INSEE 78297) has 18,603 registered voters. Its council has 35 seats; the 2026 municipal election went to a second round on 22 March. The next municipal elections are in 2032; the presidential election is on 18 April 2027.
- 18,603registered voters
- 50%turnout, 2026 round one
- 28.5%Jean-Luc Mélenchon, 2027 round one here (France: 16.8%)
The municipal election, March 2026
Round two, 22 March · 9,431 voted, 9,230 valid votes
- GUYANCOURT EN COMMUN 2026Led by François Morton · Miscellaneous left 51.4% · 4,743 · 27 seats
- ENSEMBLE, AGISSONS POUR GUYANCOURTLed by Rodolphe Barry · Miscellaneous centre 48.6% · 4,487 · 8 seats
Round one, 15 March · 9,222 voted, 9,042 valid votes
- ENSEMBLE, AGISSONS POUR GUYANCOURTMiscellaneous centre 39.4% · 3,560
- GUYANCOURT EN COMMUN 2026Miscellaneous left 39.0% · 3,524
- Union Populaire et Ecologique à GuyancourtFrance Unbowed 21.7% · 1,958
Official results, Ministère de l'Intérieur. Lists are labelled with the ministry's political "nuance"; lists in small communes carry none. The list that comes first takes half the seats as a bonus, and the rest are shared in proportion among lists over 5%.
What if the national vote changes? Every commune
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About Guyancourt
Guyancourt is a commune in Yvelines with 18,603 registered voters, the 13th largest of the département's 259 communes. At the municipal election of March 2026 49.6% of them voted, fewer than the 54.4% across Yvelines, and the list led by François Morton won 27 of the council's 35 seats after a second round.
In the first round of the 2022 presidential election the commune voted France Unbowed 35%, Ensemble (Macron camp) 29.6%, National Rally 11.7%. France Unbowed did 13 points better here than across France.
Moved to today's national polls, our projection for the 2027 first round here has Jean-Luc Mélenchon ahead on 28.5%, with Marine Le Pen on 21.7%.
The 2027 presidential election here, round one
Our national forecast for round one, carried down to Guyancourt from how it voted in 2022.
- Jean-Luc MélenchonFrance Unbowed 28.5% · France 16.8%
- Marine Le PenNational Rally 21.7% · France 34.2%
- Édouard PhilippeEnsemble (Macron camp) 16.4% · France 14.3%
- Raphaël GlucksmannSocialists 14.0% · France 13.4%
- Bruno RetailleauRepublicans 8.3% · France 7.6%
- Marine TondelierGreens 4.3% · France 2.9%
- Éric ZemmourReconquête 2.7% · France 3.8%
- Nicolas Dupont-AignanSovereigntists 1.8% · France 2.1%
- Fabien RousselCommunist Party 1.7% · France 2.0%
- Nathalie ArthaudFar left 0.5% · France 0.6%
In 2022, round one here: France Unbowed 35.0% · Ensemble (Macron camp) 29.6% · National Rally 11.7% · Greens 6.1% · Reconquête 5.0%. Each political family moves by its national change since 2022 (half uniform, half proportional), scaled so that every commune adds up to our national forecast. The national forecast →
Communes of a similar size in Yvelines
- Maisons-Laffitte17,792 voters · Miscellaneous right
- Rambouillet19,480 voters · Miscellaneous right
- Les Mureaux17,404 voters · Miscellaneous left
- Plaisir20,413 voters · Miscellaneous centre
- Elancourt16,820 voters · Les Républicains
- Chatou20,643 voters · Miscellaneous right
- Mantes-la-Jolie22,008 voters · Miscellaneous
- Trappes15,451 voters · Miscellaneous left