| School | HMC Division | Membership | Location | Age Range |
| Abingdon School | South Central (UK) | British Isles | Abingdon, United Kingdom | 11 - 18 |
| Ackworth School | North East (UK) | British Isles | Pontefract, United Kingdom | 2 - 18 |
| ACS International School Cobham | South Central (UK) | British Isles | Cobham, United Kingdom | 3 - 18 |
| Aiglon College | International | International | Ollon, Switzerland | 9 - 18 |
| AIS Saigon | International | International | , Vietnam | 1 - 18 |
| AKS Lytham | North West (UK) | British Isles | Lytham St Annes, United Kingdom | 0 - 18 |
| Albyn School | Scottish (UK) | British Isles | Aberdeen, United Kingdom | 2 - 18 |
| Aldenham School | London (UK) | British Isles | Borehamwood, United Kingdom | 0 - 18 |
| Alleyn’s School | London (UK) | British Isles | Dulwich, London, United Kingdom | 4 - 18 |
| Amadeus International School, Vienna | International | International | Wien, Austria | 3 - 18 |
| Ampleforth College | North East (UK) | British Isles | York, United Kingdom | 11 - 18 |
| Ardingly College | South East (UK) | British Isles | Haywards Heath, United Kingdom | 2 - 18 |
| Ashford School | South East (UK) | British Isles | Ashford, United Kingdom | 0 - 18 |
| Ashville Harrogate | North East (UK) | British Isles | Harrogate, United Kingdom | 2 - 18 |
| Badminton School | South West (UK) | British Isles | Bristol, United Kingdom | 3 - 18 |
| Bancroft’s School | London (UK) | British Isles | Woodford Green, Essex, United Kingdom | 7 - 18 |
| Bangkok International Preparatory & Secondary School | International | International | , Thailand | 3 - 18 |
| Bangor Grammar School | Irish | Associate (UK) | Bangor, United Kingdom | 13 - 18 |
| Barnard Castle School | North East (UK) | British Isles | Barnard Castle, United Kingdom | 4 - 18 |
| Bedales School | South Central (UK) | British Isles | Petersfield, United Kingdom | 3 - 18 |
| Bede’s School | South East (UK) | British Isles | Hailsham, United Kingdom | 13 - 18 |
| Bedford Modern School | London (UK) | British Isles | Bedford, United Kingdom | 7 - 18 |
| Bedford School | London (UK) | British Isles | Bedford, United Kingdom | 7 - 18 |
| Belfast Royal Academy | Irish | British Isles | Belfast, United Kingdom | 11 - 18 |
| Benenden School | South East (UK) | British Isles | Cranbrook, United Kingdom | 11 - 18 |
| Berkhamsted School | London (UK) | British Isles | Berkhamsted, United Kingdom | 0 - 18 |
| Birkdale School | North East (UK) | British Isles | Sheffield, United Kingdom | 4 - 18 |
| Birkenhead School | North West (UK) | British Isles | Wirral, United Kingdom | 0 - 18 |
| Bishop Wordsworth’s School | South Central (UK) | Associate (UK) | Salisbury, United Kingdom | 11 - 18 |
| Bishop’s Stortford College | East (UK) | British Isles | Bishop's Stortford, United Kingdom | 4 - 18 |
| Bloxham School | West (UK) | British Isles | Banbury, United Kingdom | 11 - 18 |
| Blundell’s School | South West (UK) | British Isles | Tiverton, United Kingdom | 11 - 18 |
| Bolton School | North West (UK) | British Isles | Bolton, United Kingdom | 0 - 18 |
| Bootham School | North East (UK) | British Isles | York, United Kingdom | 3 - 18 |
| Box Hill School | South East (UK) | British Isles | Dorking, United Kingdom | 11 - 18 |
| Bradfield College | South Central (UK) | British Isles | Reading, United Kingdom | 11 - 18 |
Abingdon School
Age range
11 - 18
Location
Park Road, Abingdon, Oxfordshire, OX14 1DE, United Kingdom
Head’s name
Michael Windsor
Ackworth School
Age range
2 - 18
Location
Pontefract Road, Ackworth, Pontefract, West Yorkshire, WF7 7LT, United Kingdom
Head’s name
Martyn Beer
ACS International School Cobham
Age range
3 - 18
Location
Portsmouth Road, Hersham, Cobham, KT11 1BL, United Kingdom
Head’s name
Robert Crowther
Aiglon College
Age range
9 - 18
Location
Avenue Centrale 61, 1885 Ollon, Switzerland
Head’s name
Nicola Sparrow
AIS Saigon
Age range
1 - 18
Location
264 Mai Chi Tho (East-West Highway), An Phu Ward, Thu Duc City, HCMC, Vietnam
Head’s name
Jon Standen
AKS Lytham
Age range
0 - 18
Location
Clifton Drive South, Lytham St Annes, Lancashire, FY8 1DT, United Kingdom
Head’s name
David Harrow
Albyn School
Age range
2 - 18
Location
17-23 Queen's Road, Aberdeen, AB15 4PB, United Kingdom
Head’s name
David Starbuck
Aldenham School
Age range
0 - 18
Location
Aldenham Road, Elstree, Radlett, Borehamwood, WD6 3AJ, United Kingdom
Head’s name
Alex Hems
Alleyn’s School
Age range
4 - 18
Location
Townley Road, Dulwich, London, SE22 8SU, United Kingdom
Head’s name
Jane Lunnon
Amadeus International School, Vienna
Age range
3 - 18
Location
Bastiengasse 36-38, 1180 Wien, Austria
Head’s name
Jeremy House
Ampleforth College
Age range
11 - 18
Location
York, YO62 4ER
Head’s name
Peter Roberts
Ardingly College
Age range
2 - 18
Location
College Road, Haywards Heath, West Sussex, RH17 6SQ, United Kingdom
Head’s name
Ben Figgis
Ashford School
Age range
0 - 18
Location
East Hill, Ashford, Kent, TN24 8PB, United Kingdom
Head’s name
Michael Hall
Ashville Harrogate
Age range
2 - 18
Location
Green Lane, Harrogate, North Yorkshire, HG2 9JP, United Kingdom
Head’s name
Rhiannon Wilkinson
Badminton School
Age range
3 - 18
Location
Westbury Road, Westbury-on-Trym, Bristol, BS9 3BA, United Kingdom
Head’s name
Jessica Miles
Bancroft’s School
Age range
7 - 18
Location
High Road, Woodford Green, England, IG8 0RF, United Kingdom
Head’s name
Alex Frazer
Bangkok International Preparatory & Secondary School
Age range
3 - 18
Location
77 Sukhumvit Road, Khlong Toei Nuea, Watthana, Bangkok 10110, Thailand
Head’s name
Duncan Stonehouse
Bangor Grammar School
Age range
13 - 18
Location
Gransha Road, Bangor, County Down, Northern Ireland, BT19 7QU, United Kingdom
Head’s name
Stephen Gilmore
Barnard Castle School
Age range
4 - 18
Location
Newgate, Barnard Castle, County Durham, DL12 8UN, United Kingdom
Head’s name
David Cresswell
Bedales School
Age range
3 - 18
Location
Church Road, Petersfield, Hampshire, GU32 2DG, United Kingdom
Head’s name
Will Goldsmith
Bede’s School
Age range
13 - 18
Location
Upper Dicker, Hailsham, East Sussex, BN27 3QH, United Kingdom
Head’s name
Peter Goodyer
Bedford Modern School
Age range
7 - 18
Location
Bedford Modern School, Bedford, Bedfordshire, MK41 7NT, United Kingdom
Head’s name
David Payne
Bedford School
Age range
7 - 18
Location
De Parys Avenue, Bedford, MK40 2TU, United Kingdom
Head’s name
Sam Baldock
Belfast Royal Academy
Age range
11 - 18
Location
Cliftonville Road, Belfast, Co Antrim, Northern Ireland, BT14 6JL, United Kingdom
Head’s name
Hilary Woods
Benenden School
Age range
11 - 18
Location
Cranbrook Road, Cranbrook, Kent, TN17 4AA, United Kingdom
Head’s name
Rachel Bailey
Berkhamsted School
Age range
0 - 18
Location
131 High Street, Berkhamsted, HP4 2DJ, United Kingdom
Head’s name
Richard Backhouse
Birkdale School
Age range
4 - 18
Location
4 Oakholme Road, Sheffield, South Yorkshire, S10 3DH, United Kingdom
Head’s name
Peter Harris
Birkenhead School
Age range
0 - 18
Location
58 Beresford Road, Wirral, Merseyside, CH43 2JD, United Kingdom
Head’s name
Paul Vicars
Bishop Wordsworth’s School
Age range
11 - 18
Location
Exeter Street, Salisbury, Wiltshire, SP1 2ED, United Kingdom
Head’s name
Stuart Smallwood
Bishop’s Stortford College
Age range
4 - 18
Location
School House, Maze Green Road, Bishop's Stortford, Hertfordshire, CM23 2PQ, United Kingdom
Head’s name
John Maguire
Bloxham School
Age range
11 - 18
Location
Banbury Road, Bloxham, Banbury, Oxfordshire, OX15 4PE, United Kingdom
Head’s name
Paul Sanderson
Blundell’s School
Age range
11 - 18
Location
Blundell's Road, Tiverton, Devon, EX16 4DN, United Kingdom
Head’s name
Bart Wielenga
Bolton School
Age range
0 - 18
Location
Chorley New Road, Bolton, BL1 4PA, United Kingdom
Head’s name
Philip Britton MBE
Bootham School
Age range
3 - 18
Location
49-57 Bootham, York, YO30 7BU, United Kingdom
Head’s name
Deneal Smith
Box Hill School
Age range
11 - 18
Location
Old London Road, Dorking, Surrey, RH5 6EE, United Kingdom
Head’s name
Hayley Robinson
Bradfield College
Age range
11 - 18
Location
Bradfield, Reading, Berkshire, RG7 6AU, United Kingdom
Head’s name
Christopher Stevens