Sebastian Kellas
Sebastian is a recognized tax professional with extensive experience in M&A, capital market and real estate transactions as well as private equity, venture capital and incentive schemes. He regularly represents his clients in tax courts in complex tax disputes. Sebastian also has deep knowledge in company law and accounting related matters. As the secretary of a working group appointed by the Ministry of Justice, he drafted the amended provisions into the Finnish Companies Act regarding cross-border mergers and demergers.
Avance Attorneys Ltd, Partner 2019–
Taxpoint Attorneys Ltd, Partner (2014–2019)
KPMG Oy Ab, Partner (2007–2014)
KPMG Oy Ab, Tax Advisor, Manager, Senior Manager and Director (1998–2006)
Helsinki Tax Office, Tax Official (1997–1998)
Master of Laws, University of Helsinki, 1995
Member of the Finnish Bar Association
Member of the Tax Expert Group of the Finnish Bar Association
Member of the International Fiscal Association (IFA)
Member of the Association for Finnish Tax Professionals (SVA)
“Sebastian Kellas is a talented structuring and tax professional with out-of-the-box solutions. Great ability to explain complex issues in layman's terms and what the implications of different scenarios would mean for the client.”
“Sebastian Kellas, tax professional with extensive experience in M&A, capital market and real estate transactions, private equity, venture capital and incentive schemes, complex tax disputes, company law and accounting related matters. He assisted us with complicated tax issues relating to offset/industrial participation projects involving the MOD and local Finnish Industry. He gave excellent, practical and timely advice.”
“Sebastian Kellas’ knowledge and customer care in his cases are excellent. I have recommended him to any of my business connections who may need a tax specialist, and they have also been very satisfied with Sebastian.”
“Sebastian Kellas knows legal cases in the field of taxation, both for companies and individuals, amazingly well. I like the way he communicates, not too formal, but still very professional and straightforward. We plan procedures so that we haven't had any cases/questions in years with authorities; can't think better tax advisor for my needs.”
The Legal 500 2026
Sebastian Kellas is ranked in Band 1 for (Tax – Finland).
“He is a very skilled lawyer.”
“He is a talented structuring and tax professional with outside the box solutions. He has a great ability to explain complex issues in layman's terms and what the implications of different scenarios would mean for the client.”
“Sebastian Kellas is the best tax lawyer in Finland.”
“Sebastian is a true expert in his field.”
“He is my go-to lawyer on tax issues.”
Chambers Europe 2026
Sebastian Kellas is ranked as “Highly Regarded” in the Real estate and Transactional tax categories.
ITR World Tax 2026
Sebastian Kellas is ranked as “Thought Leader” in Tax – Advisory.
Lexology Index 2025
“Lead partner Sebastian Kellas is most likely the best tax adviser in Finland – his skills in tax structuring and tax litigation are awesome.”
“Pragmatic approach and strong know-how within the tax field.”
The Legal 500 2025
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