MBA, degree in finance, business or accounting, etc are the qualifications required to becoming an auditor. Some employers like investment banks require chartered accountancy as the minimum qualification. External auditor requires to be a chartered accountant with any one of the professional bodies like Association of Chartered Certified Accountants, Institute of Chartered Accountants in England and Wales, Association of International Accountants, etc. The qualification to get into any such organization includes at least three GCSEs with maths and English.

Only after delivering services as an internal auditor for at least two years, can you become an external auditor. You also need to have a practising certificate and audit qualification from your professional body. Internal auditors too could further their qualifications by taking exams like Diploma in Internal Audit Practice and Advanced Diploma in Internal Auditing and Management.