Trinity's TESOL qualifications are accepted by most employers worldwide. The Trinity DipTESOL is one of only two named diploma level courses identified by Hong Kong's Education Bureau for Secondary NET positions.

Trinity is a member of professional language organisations worldwide, including the European Association for Quality Language Services (EAQUALS), the European Associating for Language Testing And Assessment (EALTA), the International Association of Teachers of English as a Foreign Language (IATEFL), Quality in TESOL Education (QuiTE) and The Association of Language Testers in Europe (ALTE).

The Trinity DipTESOL is accredited by Ofqual at Level 7 on the European Qualifications Framework (EQF) – comparable to master’s degree programmes in related subjects.

Trinity is also recognised by QuiTE (the association for the promotion of Quality in TESOL Education).

The DipTESOL is accepted by the British Council as a full TEFL Qualifying qualification for teachers in its accredited teaching organisations in the UK and in its own teaching operations overseas.