Historically, there were a variety of regional examination boards, or awarding organizations (AOs), who set examinations in their area. The 5 examination boards include:

• Assessment and Qualifications Alliance (AQA), which absorbed the following boards: AEB, JMB, NEAB, and SEG.
• Oxford, Cambridge and RSA Examinations (OCR), which absorbed the Oxford Delegacy of Local Examinations, Cambridge Local Examinations, Oxford & Cambridge Examinations Board, MEG, and RSA exam boards.
• Pearson Edexcel, which absorbed the LREB, BTEC, and ULEAC boards.
• Welsh Joint Education Committee (WJEC or CBAC), the main examining board in Wales.

Council for the Curriculum, Examinations & Assessment (CCEA), the examining board and regulator in Northern Ireland.

The examination boards operate under the supervision of Ofqual (The Office of Qualifications and Examinations Regulation) in England, Qualifications Wales in Wales, and the CCEA in Northern Ireland.

With the introduction of numbered grades, the Higher tier provides grades 9-4 and the Foundation tier provides grades 5-1.