Cian O'Sullivan

Director, BDO Dublin

Personal Tax Planning | Sports Advisory Unit


Cian is a Director in the Private Client Tax team at BDO Ireland where he advises entrepreneurs, professionals, owner-managed businesses, sportspeople, sporting organisations and entertainers on their tax planning and compliance needs.

Prior to joining BDO, he was a Director with a leading boutique private client tax practice having previously trained and worked with PwC.



Cian has extensive expertise advising private clients and is particularly experienced on the following:

  • Capital gains tax planning

  • Inheritance and gift tax planning

  • Business succession

  • Tax residency

  • Domicile and the remittance basis of taxation

  • Sportspersons tax relief

  • Sporting, artist, and charitable tax exemptions

  • Family and estate tax planning

  • Corporate tax structuring

  • Property investment structuring

  • Revenue interventions and investigations

Cian is also a Director of the BDO Sports Advisory Unit where he combines his financial expertise with his considerable experience in elite sports to advise sports professionals, clubs and National Governing Bodies on all aspects of their taxation, financial and commercial affairs. The team also advises an increasing number of high net worth entertainers/musicians having developed niche tax and financial expertise in the global sport and entertainment industries.

Cian is a Chartered Accountant and Chartered Tax Advisor and has presented on a wide range of private client tax topics to professional firms and associations in recent years.