Labour gained the Broadheath ward by just six votes as they retained control of Trafford Council at the Local Elections.
Ulrich Savary just pipped incumbent Conservative councillor Kaushik Chakroborty, polling 1,716 votes to 1,710.
Cllr Savary said it was a "real honour" to take the seat.
He said: "It's a real honour to be elected as a Labour councillor for Broadheath. Thank you to the 1716 residents who voted for me.
"I’ll keep on working hard for all residents alongside my ward colleagues to make Broadheath an even better place for all."
Cllr Savary's win helped Labour to 43 seats on the 63-strong council, the most the party has ever had.
Elsewhere in Altrincham, the Greens held on to their seats in Altrincham and Hale.
They came within just 21 votes of taking Bowdon as well, but Lisa Hancock just managed to hold it for the Conservatives.
Cllr Michael Welton, who was re-elected in Altrincham, said: "I want to thank all those who voted Green this week across Altrincham, Hale and Bowdon, and all of Trafford. We've seen some impressive results in the North and South of the borough with more people voting Green than ever before.
"Trafford Council deserves an effective opposition to the Labour council and more and more people are turning to the Green Party to provide it."
The Conservatives held on to Hale Barns & Timperley South with the Liberal Democrats comfortably holding Timperley Central and Timperley North.
The full results in Altrincham wards:
Altrincham (turnout - 43%) - GREENS HOLD
- Julie Bernadette Ashall (Conservative) - 810
- Will Franks (Labour) - 518
- Miniaci Mario (Liberal Democrats) - 103
- Michael Welton (Green) - 1927
Bowdon (turnout 47.9%) - CONSERVATIVES HOLD
- Bridget Mary Green (Green) - 1698
- Lisa Hancock (Conservative) - 1719
- Kate Lamerton (Labour) - 322
- Paul James Swansborough (Reform UK) - 174
- Ludo Tolhurst-Cleaver (Liberal Democrats) - 82
Broadheath (47.4%) - LABOUR GAIN
- Andrew Brougham-Holland (Reform UK) - 219
- Kaushik Chakroborty (Conservative) - 1710
- Stephen John Farndon (Independent) - 56
- Chris Marritt (Liberal Democrats) - 179
- Ulrich Stephane Bertrand Savary (Labour) - 1716
- Alexander Young (Green) - 271
Hale (turnout 47.4%) - GREENS HOLD
- Natalie Shalom (Conservative) - 1351
- Josh Sindler (Labour) - 436
- Jason John Stack (Liberal Democrats) - 135
- Owain Sutton (Green) - 1751
Hale Barns & Timperley South (turnout 43%) - CONSERVATIVES HOLD
- Andrew Davies ( Reform UK) - 201
- Gawain Glenton (Labour) - 336
- Marc Steven Ramsbottom (Liberal Democrats) - 1076
- John Ross (Green) - 223
- Michael James Taylor ( Conservative) - 1385
Timperley Central (turnout 43%) - LIB DEMS HOLD
- Harry John Atack (Conservative) - 751
- James William Brooke-Taylor (Green) - 189
- Simon Edward Lepori (Liberal Democrats) - 1808
- Mark Anthony Nesbitt (Labour) - 623
- Deborah Rhodes (Reform UK) - 245
Timperley North (turnout 46.4%) - LIB DEMS HOLD
- Anand Rao Chinthala (Conservative) - 638
- Rachel Fell (Labour) - 754
- Meena Minnis (Liberal Democrats) - 2329
- Aagash Vadera (Green) - 259
