The Yearbook & Directory of Ireland's international financial services industry
Thursday, 24th June 2021

O'Sullivan, Brian

Firm: Grant Thornton
Position: Partner, Audit and Assurance
Address: 13-18 City Quay, Dublin 2, D02 NY19
Phone: +353 1 408 6977

Special Areas:

Brian has been promoted internally to Partner, having spent his recent years contributing heavily to the continued growth of our Financial Services Audit department, specialising in banking and asset management. Brian will be part of an exciting new joint initiative between the Grant Thornton US and Irish firms, whereby when the current travel restrictions permit then Brian will be based in New York and will operate across the Grant Thornton US Audit and Advisory teams, further strengthening and developing international relationships and reach for the Irish firm. Brian re-joined the firm as a Director in 2018 having begun his early career with Grant Thornton Ireland before spending a number of years working with a Big Four firm and local pillar bank.

Brian has led the audit of a London Stock Exchange listed banking group with full scope subsidiaries across Europe. This encompassed ISRE 2410 interim reviews, approved year-end preliminary announcements and public announcements of annual reports.

He was also an Associate Director on the audit of one of Ireland’s three largest banks having successfully transitioned the audit from another Big four firm. During his tenure on this engagement he played leading roles on the audit of Corporate, Consumer and Central divisions, including review of impairment models, sub-participation following the de-leveraging of NPL portfolios, subsidiary disposals and ECB regulatory finding responses.

His portfolio of clients has included SOX reporting, multi-national group audits, banks, LSE listed clients, section 110's, SPV's PCAOB experience and single entity funds.

In addition to his practice experience, Brian has had significant exposure to the practical processes of the industry having spent over 3 years working within the corporate lending department of AIB and developed internal cash-flow models.


Brian was a Qualified Financial Advisor during his time with AIB and is a member of Chartered Accountants Ireland (CAI). He was also the Irish representative for EMEIA on an IFRS16 steering committee for a Big Four Firm prior to commencing back with Grant Thornton.