| School | HMC Division | Membership | Location | Age Range |
| Bangor Grammar School | Irish | Associate (UK) | Bangor, United Kingdom | 13 - 18 |
| Belfast Royal Academy | Irish | British Isles | Belfast, United Kingdom | 11 - 18 |
| Campbell College | Irish | British Isles | Belfast, United Kingdom | 3 - 18 |
| Clongowes Wood College | Irish | British Isles | Naas, Republic of Ireland | 12 - 18 |
| Coleraine Grammar School | Irish | British Isles | Coleraine, United Kingdom | 11 - 18 |
| Friend’s School Lisburn | Irish | British Isles | Lisburn, United Kingdom | 12 - 18 |
| Methodist College (Belfast) | Irish | British Isles | Belfast, United Kingdom | 11 - 18 |
| Rockport School | Irish | British Isles | Holywood, United Kingdom | 2 - 18 |
| St Columba’s College, Dublin | Irish | British Isles | Dublin, Republic of Ireland | 12 - 18 |
| The King’s Hospital School | Irish | British Isles | Dublin, Republic of Ireland | 12 - 18 |
| The Royal Belfast Academical Institution | Irish | British Isles | Belfast, United Kingdom | 11 - 18 |
| The Royal School Armagh | Irish | British Isles | Armagh, United Kingdom | 4 - 18 |
| The Royal School, Dungannon | Irish | British Isles | Dungannon, United Kingdom | 11 - 18 |
Bangor Grammar School
Age range
13 - 18
Location
Gransha Road, Bangor, County Down, Northern Ireland, BT19 7QU, United Kingdom
Head’s name
Stephen Gilmore
Belfast Royal Academy
Age range
11 - 18
Location
Cliftonville Road, Belfast, Co Antrim, Northern Ireland, BT14 6JL, United Kingdom
Head’s name
Hilary Woods
Campbell College
Age range
3 - 18
Location
Belmont Road, Belfast, BT4 2ND, United Kingdom
Head’s name
Jonathan Anderson
Clongowes Wood College
Age range
12 - 18
Location
Clane, Naas, County Kildare, W91 DN40, Republic of Ireland
Head’s name
Christopher Lumb
Coleraine Grammar School
Age range
11 - 18
Location
23-33 Castlerock Road, Coleraine, County Londonderry, Northern Ireland, BT51 3LA, United Kingdom
Head’s name
David Carruthers
Friend’s School Lisburn
Age range
12 - 18
Location
6 Magheralave Road, Lisburn, UK
Head’s name
Stephen Moore
Methodist College (Belfast)
Age range
11 - 18
Location
1 Malone Road, Belfast, BT9 6BY, United Kingdom
Head’s name
Jenny Lendrum
Rockport School
Age range
2 - 18
Location
15 Rockport Road, Craigavad, Holywood, BT18 0DD
Head’s name
George Vance
St Columba’s College, Dublin
Age range
12 - 18
Location
Whitechurch, Dublin 16, D16 CH92, Republic of Ireland
Head’s name
Mark Boobbyer
The King’s Hospital School
Age range
12 - 18
Location
Old Lucan Road, Palmerstown, Co. Dublin, D20 V256, Ireland
Head’s name
Mark Wallace
The Royal Belfast Academical Institution
Age range
11 - 18
Location
College Square East, Belfast, Co. Antrim, Northern Ireland, BT1 6DL, United Kingdom
Head’s name
Janet Williamson
The Royal School Armagh
Age range
4 - 18
Location
College Hill, Armagh, Northern Ireland, BT61 9DH, United Kingdom
Head’s name
Graham Montgomery
The Royal School, Dungannon
Age range
11 - 18
Location
2 Ranfurly Road, Dungannon, Northern Ireland, BT71 6EG, United Kingdom
Head’s name
David Burnett