| School | HMC Division | Membership | Location | Age Range |
| Kimbolton School | East (UK) | British Isles | Huntingdon, United Kingdom | 4 - 18 |
| King Edward VI School | South Central (UK) | British Isles | Southampton, United Kingdom | 11 - 18 |
| King Edward’s School (Bath) | South West (UK) | British Isles | Bath, United Kingdom | 3 - 18 |
| King Edward’s School (Witley) | South East (UK) | British Isles | Godalming, United Kingdom | 11 - 18 |
| King Edward’s School Birmingham | West (UK) | British Isles | Birmingham, United Kingdom | 11 - 18 |
| King William’s College | North West (UK) | British Isles | Castletown, Isle of Man | 4 - 18 |
| King’s Bruton | South West (UK) | British Isles | Bruton, United Kingdom | 13 - 18 |
| King’s College (Taunton) | South West (UK) | British Isles | Taunton, United Kingdom | 13 - 18 |
| King’s College School, Wimbledon | London (UK) | British Isles | Wimbledon, London, United Kingdom | 7 - 18 |
| King’s College, Auckland | International | International | Auckland, New Zealand | |
| King’s College, The British School of Madrid | International | International | Madrid, Spain | 0 - 18 |
| King’s Ely | East (UK) | British Isles | Ely, United Kingdom | 2 - 18 |
| King’s School Rochester | South East (UK) | British Isles | Rochester, United Kingdom | 3 - 18 |
| Kingston Grammar School | London (UK) | British Isles | Kingston upon Thames, Surrey, United Kingdom | 11 - 18 |
| Kingswood School, Bath | South West (UK) | British Isles | Bath, United Kingdom | 11 - 18 |
| Kirkham Grammar School | North West (UK) | British Isles | Preston, United Kingdom | 3 - 18 |
| Kolej Tuanku Ja’afar | International | International | Mantin, Malaysia | 4 - 18 |
| Lady Eleanor Holles School | London (UK) | British Isles | Hampton, Richmond upon Thames, United Kingdom | 7 - 18 |
| Lancing College | South East (UK) | British Isles | Lancing, United Kingdom | 13 - 18 |
| Langley School | East (UK) | British Isles | Norwich, United Kingdom | 2 - 18 |
| Latymer Upper School | London (UK) | British Isles | Hammersmith, London, United Kingdom | 11 - 18 |
| Leicester Grammar School | East (UK) | British Isles | Leicester, United Kingdom | 3 - 18 |
| Leighton Park School | South Central (UK) | British Isles | Reading, United Kingdom | 11 - 18 |
| Lincoln Minster School | East (UK) | British Isles | Lincoln, United Kingdom | 4 - 18 |
| Lingfield College | South East (UK) | British Isles | Lingfield, United Kingdom | 2 - 18 |
| Lomond School | Scottish (UK) | British Isles | Helensburgh, United Kingdom | 3 - 18 |
| Lord Wandsworth College | South Central (UK) | British Isles | Long Sutton, United Kingdom | 11 - 18 |
| Loretto School | Scottish (UK) | British Isles | East Lothian, United Kingdom | 3 - 18 |
| Loughborough Grammar School | East (UK) | British Isles | Loughborough, United Kingdom | 10 - 18 |
| Magdalen College School | South Central (UK) | British Isles | Oxford, United Kingdom | 7 - 18 |
| Malvern College | West (UK) | British Isles | Malvern, United Kingdom | 13 - 18 |
| Manchester High School for Girls | North West (UK) | British Isles | Manchester, United Kingdom | 4 - 18 |
| Marlborough College | South Central (UK) | British Isles | Marlborough, United Kingdom | 13 - 18 |
| Marlborough College, Malaysia | International | International | Iskandar Puteri, Malaysia | 3 - 18 |
| Merchant Taylors’ Boys’ School, Crosby | North West (UK) | British Isles | Liverpool, United Kingdom | 4 - 18 |
| Merchant Taylors’ School, Northwood | London (UK) | British Isles | Hillingdon, London, United Kingdom | 11 - 18 |
Kimbolton School
Age range
4 - 18
Location
Kimbolton, Huntingdon, Cambridgeshire, PE28 OEA, United Kingdom
Head’s name
Will Chuter
King Edward VI School
Age range
11 - 18
Location
Wilton Road, Southampton, Hampshire, SO15 5UQ, United Kingdom
Head’s name
Neal Parker
King Edward’s School (Bath)
Age range
3 - 18
Location
North Roadd, Claverton Down, Bath, BA2 6HU, United Kingdom
Head’s name
Martin Boden
King Edward’s School (Witley)
Age range
11 - 18
Location
Godalming, Surrey, GU8 5SG, United Kingdom
Head’s name
Joanna Wright
King Edward’s School Birmingham
Age range
11 - 18
Location
King Edward's School, Edgbaston Park Road, Birmingham, B15 2UA, United Kingdom
Head’s name
Katy Ricks
King William’s College
Age range
4 - 18
Location
Castletown, IM9 1TP, Isle of Man
Head’s name
Damian Henderson
King’s Bruton
Age range
13 - 18
Location
The Plox, Bruton, Somerset, BA10 OED, United Kingdom
Head’s name
Ian Wilmshurst
King’s College (Taunton)
Age range
13 - 18
Location
South Rd, Taunton, TA1 3LA, United Kingdom
Head’s name
Michael Sloan
King’s College School, Wimbledon
Age range
7 - 18
Location
Southside, Wimbledon Common, London SW19 4TT, United Kingdom
Head’s name
Anne Cotton
King’s College, Auckland
Age range
Location
Golf Avenue, Otahuhu 1640, Auckland, New Zealand
Head’s name
Simon Lamb
King’s College, The British School of Madrid
Age range
0 - 18
Location
Paseo de Los Andes 35, Soto de Vinuelas, Madrid, 28760, Spain
Head’s name
Matthew Taylor
King’s Ely
Age range
2 - 18
Location
The Old Palace, Ely, Cambridgeshire, CB7 4EW, United Kingdom
Head’s name
John Attwater
King’s School Rochester
Age range
3 - 18
Location
Satis House, Rochester, Kent, ME1 1TE, United Kingdom
Head’s name
Ben Charles
Kingston Grammar School
Age range
11 - 18
Location
70 London Road, Kingston upon Thames, Surrey, KT2 6PY, United Kingdom
Head’s name
Stephen Lehec
Kingswood School, Bath
Age range
11 - 18
Location
Lansdown Road, Bath, BA1 5RG, United Kingdom
Head’s name
Andrew Gordon-Brown
Kirkham Grammar School
Age range
3 - 18
Location
Ribby Road, Preston, Lancashire, PR4 2BH, United Kingdom
Head’s name
Deborah Parkinson
Kolej Tuanku Ja’afar
Age range
4 - 18
Location
Kolej Tuanku Ja'afar, Mantin, Negeri Sembilan, 71700, Malaysia
Head’s name
Glenn Moodie
Lady Eleanor Holles School
Age range
7 - 18
Location
102 Hanworth Road, Hampton, Middlesex, TW12 3HF, UK
Head’s name
Rowena Cole
Lancing College
Age range
13 - 18
Location
Lancing, West Sussex, BN15 0RW, United Kingdom
Head’s name
Dominic Oliver
Langley School
Age range
2 - 18
Location
Langley Park, Loddon, Norwich, NR14 6BJ, United Kingdom
Head’s name
Jon Perriss
Latymer Upper School
Age range
11 - 18
Location
237 King Street, Hammersmith, London, W6 9LR, United Kingdom
Head’s name
Su Wijeratna
Leicester Grammar School
Age range
3 - 18
Location
London Road, Leicester, Leicestershire, LE8 9FL, United Kingdom
Head’s name
John Watson
Leighton Park School
Age range
11 - 18
Location
Shinfield Road, Reading, Berkshire, RG2 7ED, United Kingdom
Head’s name
Matthew Judd
Lincoln Minster School
Age range
4 - 18
Location
Upper Lindrum Street, Lincoln, KN2 5RW, United Kingdom
Head’s name
Jon Tyler
Lingfield College
Age range
2 - 18
Location
St Piers Lane, Lingfield, Surrey, RH7 6PH, United Kingdom
Head’s name
Richard Bool
Lomond School
Age range
3 - 18
Location
10 Stafford Street, Helensburgh, Argyll & Bute, Scotland, G84 9JX, United Kingdom
Head’s name
Claire Chisholm
Lord Wandsworth College
Age range
11 - 18
Location
Long Sutton, Hampshire, RG29 1TB, United Kingdom
Head’s name
Adam Williams
Loretto School
Age range
3 - 18
Location
1-7 Linkfield Road, East Lothian, Scotland, EH21 7RE, United Kingdom
Head’s name
Graham Hawley
Loughborough Grammar School
Age range
10 - 18
Location
Burton Walks, Loughborough, Leicestershire, LE11 2DU, United Kingdom
Head’s name
Helen Foster
Magdalen College School
Age range
7 - 18
Location
Magdalen College, Oxford, OX4 1DZ, United Kingdom
Head’s name
Helen Pike
Malvern College
Age range
13 - 18
Location
College Road, Malvern, Worcestershire, WR14 3DF, United Kingdom
Head’s name
Keith Metcalfe
Manchester High School for Girls
Age range
4 - 18
Location
Grangethorpe Road, Manchester, England, M14 6HS, United Kingdom
Head’s name
Helen Jeys
Marlborough College
Age range
13 - 18
Location
Bath Road, Marlborough, Wiltshire, SN8 1PA, United Kingdom
Head’s name
Louise Moelwyn Hughes
Marlborough College, Malaysia
Age range
3 - 18
Location
Jalan Marlborough, Puteri Harbour, 79200 Iskandar Puteri, Johor, Malaysia
Head’s name
Alan Stevens
Merchant Taylors’ Boys’ School, Crosby
Age range
4 - 18
Location
186 Liverpool Rd, Crosby, Liverpool L23 0QW, United Kingdom
Head’s name
Michael Alderson
Merchant Taylors’ School, Northwood
Age range
11 - 18
Location
Sandy Lodge, Northwood, Middlesex, HA6 2HT, United Kingdom
Head’s name
Simon Everson