What our Clients Say

Having moved to McGuinness O’Neill several years ago I can now sleep at night in the knowledge my corporate accounts is in safe hands. Things are done efficiently on time and without fuss. Nothing appears to be a problem and we receive a response to any queries promptly
Franklins Estate Agents

We have been very pleased with the service provided by Mc Guinness O Neill during our first year of business. Mc Guinness O Neill made the start-up process simple, streamlined and advised us well throughout the entire process. It can be a bit daunting when starting a new business and we had a lot of questions during our first year while getting to grips with dealing with revenue, paying suppliers, paying staff etc. Mc Guinness O Neill were always available to guide us through the process and have also been very proactive in offering the latest developments in accountancy management software that have greatly helped us with time management on the administration of our accounts and as a small business this has been invaluable.
Built Interiors Limited

We have been working with Cathy and her team for over 20 years. Over the years our business has changed considerably, and the advice provided by Mc Guinness O Neill has always been remarkable. We find the services provided by Mc Guinness O Neill to be efficient and reliable. They are always very responsive to any queries raised and give great attention to detail when preparing our annual accounts.
The Lunch Box

Mc Guinness O’Neill have been our accountants for 4 years now and we are extremely happy with the services provided. We have been with them since we first set up the company.

They guided us and helped us set up our business including cash projections, business planning, financing etc.

Since then they have supported us with new business ventures and always made us feel like no task was too big or too small

Tank & Skinnys

We recently switched accountants to McGuinness ONeill and the transition was very smooth. We find Cathy and her team highly professional and they completely understand our business needs. We would have no hesitation in recommending McGuinness ONeill to any business and we look forward to continuing to do business with McGuinness ONeill into the future
Lough Swilly Test Centre Limited

Working with Mc Guinness O’Neill was one of the best decisions I made when opening my business, everything was made simple yet very professional. All staff members are highly approachable and friendly.

They pay great attention to every detail of work business & personal, Highly recommend.

The Beauty Studio by Megan

I have been a client of Mc Guinness O Neill for over 19 years. Cathy & staff provide an excellent service.

They are very efficient and always helpful with all enquiries

An Siopa Gruaige

I am a non-resident Landlord of a 4-bedroom property in North West Ireland and McGuinness O Neill have for a number of years acted as my personal tax accountants and advisers.

They have always provided an outstanding professional service with compassion and consideration. I would not hesitate to recommend them to anyone

Margaret D


My son Yannick and myself, non-residents, both purchased property in County Donegal. Mc Guinness O Neill provides us a fantastic service. They always help us very fast with a crystal clear answer to our inquiries.

Freddy and Yannick – Belgium.

Non-resident Landlords.