| Fullname: | Chelsea Football Club Under-21s and Academy |
| Clubname: | Chelsea Under-21s and Academy |
| Nickname: | The Blues The Young Blues |
| Ground: | Kingsmeadow Cobham Training Centre Stamford Bridge |
| Capacity: | 4,850 (Kingsmeadow) 40,173 (Stamford Bridge) |
| Owner: | BlueCo[1] |
| Chairman: | Todd Boehly |
| Manager: | Filipe Coelho (U21) Hassan Sulaiman (U18) |
| League: | Premier League 2 (under-21s) U18 Premier League (academy) |
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Chelsea F.C. Under-21s, previously referred to as the Development Squad, are the development team of Chelsea Football Club. They play in the Premier League 2, which is the top level of reserve football in England. They were the champions in the 2013–14 and 2019–20 seasons. The team mainly consists of under-21 players at the club, although senior players occasionally feature, when recovering from injuries or otherwise not in the first team. The under-21 team is managed by Filipe Coelho and the under-18 team is managed by Hassan Sulaiman.
Chelsea F.C. Academy is the under-18 team of Chelsea Football Club. It is a member of the Professional U18 Development League. They have won the FA Youth Cup nine times, including five consecutive titles between 2014 and 2018. The academy has produced many successful players such as the brothers Ron and Allan Harris, Peter Bonetti, Bobby Tambling, Barry Bridges, Bert Murray, John Hollins, Peter Osgood, Ray Wilkins, Graeme Le Saux, Bobby Smith, Terry Venables, Jimmy Greaves, John Terry, Mason Mount, Reece James and Conor Gallagher. Chelsea are the only English club to reach the final of the UEFA Youth League, winning it twice in four final appearances.
The under-21 team play their home games at Kingsmeadow, while the under-18s play at the club's Cobham Training Centre in Cobham, Surrey. Both teams occasionally use the club's home ground Stamford Bridge for important matches.
| Under-21s head coach | Filipe Coelho |
| Under-21s assistant | Jack Mesure |
| James Simmonds | |
| Under-18s head coach | Hassan Sulaiman |
| Under-18s assistant | Andy Ross |
| Jimmy Smith | |
Gerry Baker
Samuele Dalla Bona
Frank Sinclair
Junior Mendes
Muzzy Izzet
Toni Silva
Jóhann Berg Guðmundsson
Ben Sahar Fabio Borini Jermaine Beckford Shaun Cummings Anthony Grant
Dominic Poleon
Mbark Boussoufa Bradley Woods-Garness
Richard Bakary
Bertrand Traoré
Iké Ugbo
Ian Poveda
Victorien Angban Jérémie Boga
Michael Olise
Tariq Lamptey
Louie Annesley Aliu Djaló
Nathan Moriah-Welsh Di'Shon Bernard Kasey Palmer Rohan Ince
Ola Aina
Marcin Bułka
Aziz Deen-Conteh Kevin Wright Gökhan Töre
Armando Broja
Ben Elliott Omari Hutchinson
Lucas Bergström Cesare Casadei Dujuan Richards Jon Russell
