Triple accreditation (or Triple Crown accreditation) is the combination of accreditations awarded to 89 business schools worldwide as of May 2018 (up from 74 in May 2016) by the three largest and most influential business school accreditation organizations:
Of the 13,670 schools offering business degree programs worldwide, only 90 have triple accreditation as of August 2018.
A major reason for the small number of triple-accredited institutions in the world is the requirement of the Association of MBAs that AMBA-accredited business schools should only admit MBA applicants with at least three years of full-time post-graduation work experience. Some analysts claim that most top US business schools cannot meet this criterion as they sometimes (though rarely) admit applicants with only a bachelor's degree and little or no work experience. They claim that it is why triple-crown accreditation is pursued primarily by European institutions. However, it is not the case when some (former) triple accredited institutes, City University of Hong Kong for example, only require applicants having "relevant work experience is desirable (though not specifically required)".
Differences in accreditation
Each of the three institutions assesses a business school according to different criteria and scope:
Scope of business school accreditation for AACSB, EQUIS and AMBA
- AACSB has the broadest scope, as it accredits management and accounting programs at the entire university (e.g. management programs at the business school and the school of engineering) and grants university-wide accreditation.
- AMBA has the most focused scope as it accredits only the business school's portfolios of MBA programs (full-time, part-time, executive, distance-learning), MBM programs (including MSc International Management) and DBA (also known as DMgt in China).
- EQUIS's scope ranks in the middle, as it accredits the business school but not the university and not specific portfolios of programs.
- Duration of the accreditation process
- AACSB: 2–7 years
- AMBA: 9–18 months
- EQUIS: 2–3 years
- AACSB: full re-accreditation every 5 or 10 years (the 10-year accreditation is being phased out)
- AMBA: full re-accreditation every 3 or 5 years (1-year accreditation is a possible outcome of reaccreditation in exceptional circumstances)
- EQUIS: full re-accreditation every 3 or 5 years
- AACSB's peer review team includes deans and business school administrators.
- AMBA's assessment team includes deans, associate deans, program directors and one AMBA representative.
- EQUIS's team includes three deans and one corporate representative.
- Evaluation report content
- AACSB's report reflects compliance with the AACSB standards
- AMBA's report includes compliance with criteria, conditions and recommendations
- EQUIS's report reflects compliance with the EQUIS standards
- AACSB: 77 pages for Business Accreditation; 36 pages for Accounting Accreditation
- AMBA: 24 pages (9 pages for MBA; 9 pages for MBM; 6 pages for DBA)
- EQUIS: 71 pages
- Quantitative vs Qualitative
- AACSB has more quantitative criteria (checklists)
- AMBA has more qualitative criteria
- EQUIS is in the middle (between AACSB and AMBA)
- AACSB conducts the evaluation against the school's own mission, so AACSB has no internationalization requirement unless internationalization is part of the school's mission.
- AMBA has internationalization criteria for research, curriculum and student enrolment. However, these are reviewed in a regional context for less internationalized regions (e.g. Latin America and Russia).
- EQUIS has strict requirements on internationalization.
- AACSB: prescribed faculty ratios (AQ/PQ ratio)
- AMBA: no prescribed faculty-to-students ratio
- EQUIS: prescribed minimum numbers of faculty
Feb 2014 Survey Results among MBA applicants, in response to the question: "Which of the following accreditations is/was most important to you when choosing a business school?" 
- AACSB disapproves of heavy use of visiting faculty.
- AMBA allows the visiting faculty model, as long as the visiting faculty are managed by the core faculty (and as long as the quality and course content is monitored).
- EQUIS disapproves of heavy use of visiting faculty.
- AACSB requires research in line with the mission of the school.
- AMBA requires research and publications in international refereed journals or proof of impactful research at national level.
- EQUIS requires research with an international dimension.
- Program-specific criteria
- AACSB has no program-specific standards since it evaluates the entire university.
- AMBA has program-specific criteria such as:
- at least 3 years of full-time work experience for all admitted MBA students;
- at least 500 contact hours (scheduled class hours) for a full-time MBA curriculum and a minimum of 120 contact hours for a distance-learning MBA;
- at least 20 students enrolled in an MBA program;
- EQUIS has some program-specific standards in the context of the evaluation of the entire business school.
- Accreditation fees
- AACSB: 47,000 USD for initial business accreditation (or 63,500 USD for both business and accounting accreditation). In addition, an annual business accreditation fee is charged: 4,500 USD annually for a 5-year accreditation cycle or 2,500 USD annually for a 10-year accreditation cycle.
- AMBA: 22,000 GBP for initial accreditation or 15,000 GBP for re-accreditation.
- EQUIS: 52,800 EUR for a 5-year initial accreditation or re-accreditation and 46,200 EUR for a 3-year initial accreditation or re-accreditation.
There are 87 triple-accredited schools based in 33 countries and territories as of March 2018:
- Audencia Nantes, Nantes
- EDHEC (École des hautes études commerciales du nord), Lille & Nice
- EMLYON Business School, Lyon
- ESSCA School of Management, Angers, Paris, Shanghai, Budapest, Lyon, Bordeaux and Aix-en-Provence
- ESSEC Business School, Paris, Cergy, Singapore, Rabat, Mauritius
- ESC Rennes School of Business, Rennes
- ESCP-Europe (École supérieure de commerce de Paris — Europe), Paris
- Grenoble School of Management, Grenoble
- HEC Paris (Ecole des Hautes Etudes Commerciales), Paris
- IÉSEG School of Management (Lille, Paris)
- INSEAD (Institut Européen d'Administration des Affaires), Fontainebleau & Singapore
- KEDGE Business School, Bordeaux and Marseille
- NEOMA Business School, Rouen and Reims
- Toulouse Business School, Toulouse
- Skema Business School, Sophia Antipolis, Lille, Paris, Raleigh (NC, USA), Souzhou (China), Belo Horizonte (Brasil)
- Adam Smith Business School, University of Glasgow, Glasgow
- Alliance Manchester Business School, University of Manchester, Manchester
- Aston Business School, Aston University, Birmingham
- Birmingham Business School, University of Birmingham, Birmingham
- Bradford University School of Management, University of Bradford, Bradford
- Cass Business School, City University London, London
- Cranfield School of Management, Cranfield University, Bedfordshire
- Durham University Business School, Durham University, Durham
- University of Edinburgh Business School, Edinburgh University, Edinburgh
- ESCP Europe, London
- University of Exeter Business School, University of Exeter, Devon
- Henley Business School, University of Reading, Henley-on-Thames and Reading
- Imperial College Business School, London
- Lancaster University Management School, Lancaster University, Lancaster
- Leeds University Business School, University of Leeds, Leeds
- London Business School, London
- Loughborough University School of Business and Economics, Loughborough University, Loughborough
- Newcastle University Business School, Newcastle University, Newcastle upon Tyne
- Open University Business School
- University of Sheffield Management School, University of Sheffield, Sheffield
- Strathclyde Business School, University of Strathclyde, Glasgow
- Warwick Business School, University of Warwick
Top schools without triple accreditation
One reason for this is that a (small) number of top business schools choose not to allocated the work resource and incur the financial cost required for international accreditation and rely only on accreditation by their national accrediting body (usually the country's education ministry).
Another reason is that the top schools in some regions do not meet one or more of the detailed criteria of the accrediting institutions and choose not to amend their policy. Notable examples are some top US business schools: Harvard Business School, Wharton, Stanford GSB, Columbia Business School, Chicago Booth, Tuck School of Business, etc., which do not meet AMBA's mandatory three-year student-work-experience requirement for all MBA students.
A third reason is that most of the 509 schools that have obtained AACSB accreditation in the US and Canada (either via the standard accreditation process or via the granting of accreditation based on their reputation as top schools) do not look outside of North America for further validation, such as through European or British accreditation.