Trusted accounting, tax compliance, and strategic financial advisory services for individuals, sole traders, SMEs, and companies across Ireland.
Years of Experience
Clients Served
Client Retention Rate
O'Sullivan & Associates is a leading firm of Chartered Accountants based in the heart of Dublin. Founded in 1999, we have built our reputation on providing clear, practical, and technically sound financial advice tailored to the Irish regulatory environment.
We serve a diverse client base, from individual taxpayers and sole traders to growing SMEs and established companies. Our team stays current with all aspects of Irish tax law, the Companies Act 2014, Revenue Commissioners requirements, and financial reporting standards including FRS 102 and FRS 105.
From day-to-day bookkeeping to strategic tax planning, we provide the full spectrum of professional services your business needs.
Complete management of your tax obligations including Income Tax (Form 11), Corporation Tax (CT1), and VAT returns. We ensure timely filing via ROS and maximise all available credits and reliefs.
Learn moreStrategic tax planning to optimise your position. We advise on Entrepreneur Relief, Retirement Relief, R&D Tax Credits, Start-Up Relief for companies, and the Employment Investment Incentive (EII) scheme.
Learn morePreparation of statutory financial statements under FRS 102, FRS 102 Section 1A (small entities), and FRS 105 (micro-entities). We also advise on audit exemption criteria for qualifying small companies.
Learn moreFull payroll management under PAYE Modernisation with real-time reporting to Revenue. We handle PRSI, USC, BIK calculations, small benefit exemptions, and all employer obligations.
Learn moreCompany formation advice, CRO annual return filings (B1), maintenance of statutory registers, and compliance with directors' obligations under the Companies Act 2014.
Learn moreExpert guidance on choosing the right structure: sole trader, partnership, or limited company. We analyse the tax efficiency, liability exposure, and compliance burden of each option for your situation.
Learn moreStay informed about the rates that matter most to your business and personal finances.
Rates applicable for tax year 2025. Standard rate cut-off point for a single person: €42,000. Please contact us for personalised advice.
Never miss a deadline. We manage your compliance calendar so you can focus on your business.
Small companies with a December year-end must pay preliminary Corporation Tax by the 23rd day of the month prior to year-end (or 21st for non-ROS).
Annual Return Date (ARD) depends on your company’s incorporation date. Late filings incur penalties and risk loss of audit exemption.
Corporation Tax return (CT1) and balance of tax due for December year-end companies. ROS extended deadline applies.
Paper filing deadline for Form 11. Preliminary tax for 2025 and balance due for 2024. ROS filers typically receive an extension to mid-November.
Extended pay-and-file deadline for Income Tax filers using ROS (Revenue Online Service). Exact date confirmed annually by Revenue.
Capital Gains Tax payment deadline for disposals made between 1 January and 30 November 2025.
We combine deep technical expertise with a personal, accessible approach to every client relationship.
Our team has extensive knowledge of the Irish tax system, Revenue Commissioners procedures, and all available reliefs and incentives including R&D credits, EII, and Start-Up Relief.
We don't just file returns. We actively identify opportunities to reduce your tax burden through legitimate planning, succession strategies, and structure optimisation.
If selected for a Revenue audit or compliance intervention, we manage the entire process, liaise with Revenue on your behalf, and protect your interests at every stage.
We translate complex financial and tax matters into clear, understandable guidance so you can make informed decisions about your business and personal finances.
We leverage modern cloud accounting platforms and ROS to deliver efficient, real-time financial reporting and ensure you always have visibility over your numbers.
For complex matters such as transfer pricing, cross-border transactions, or EU regulatory requirements, we collaborate with specialist advisors to ensure comprehensive coverage.
Get a quick estimate of your Irish income tax, USC, and PRSI obligations. For precise calculations, please consult with our team.
Enter your gross annual income for a quick breakdown of your 2025 tax liabilities.
Hear from some of the clients who rely on our expertise to manage their financial obligations and grow their businesses.
O'Sullivan & Associates have been our accountants for over eight years. They guided us through a Revenue audit with minimal disruption and identified significant tax savings we had been missing. Highly recommended.
When I was starting my business, I wasn't sure whether to operate as a sole trader or form a limited company. The team gave me a thorough comparison and helped me make the right decision for my circumstances. Their ongoing support has been invaluable.
Excellent service across payroll, VAT, and annual accounts. They handle our PAYE modernisation reporting flawlessly and always explain things in plain English. A really professional outfit that genuinely cares about their clients.
Answers to the questions we hear most often from clients and prospective clients.
Reach out for an initial consultation. We'll take the time to understand your situation and explain how we can help, with no obligation.
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