Grant Thornton Advisors completes deal with Polish firm; expands multinational platform in Europe

Press release

Grant Thornton Advisors completes deal with Polish firm; expands multinational platform in Europe

23 Jan 2026

CHICAGO and WARSAW, January 23, 2026 – The Grant Thornton Advisors platform has completed a transaction that will add Grant Thornton Poland to the multinational platform it created last year. The move will deepen the platform’s footprint in Europe and signals its continued investment in cross-border professional services.

The transaction, backed by an investor group led by New Mountain Capital, brings Grant Thornton Poland’s more than 1,200 professionals and US$70 million in annual revenue into a platform of 17 firms worldwide, eight of which are based in Europe — namely Grant Thornton firms in Ireland, France, Spain, Netherlands, Belgium, Luxembourg, the Channel Islands and Switzerland/Liechtenstein. 

Over the past decade, Grant Thornton Poland has tripled its headcount and increased its revenues fivefold, growing both organically and through mergers and acquisitions. The firm is a trusted provider of audit, tax, legal, payroll and accounting services, and is also known for its strong advisory services for mergers and acquisitions as well as digital consulting.

The expansion in Europe complements the platform’s growing presence in the Americas, the Middle East and Asia-Pacific, where recent transactions include firms in Brazil, the United Arab Emirates and New Zealand. The platform has also added specialized US firms such as Auxis, a pioneer in outsourcing and business modernization, and Stax, a leader in commercial due diligence and value creation.

The expanded platform will continue to be part of the Grant Thornton International Limited network, which comprises member firms in more than 150 markets worldwide.

About Grant Thornton 

Grant Thornton delivers professional services in the US through two specialized entities: Grant Thornton LLP, a licensed, certified public accounting (CPA) firm that provides audit and assurance services ― and Grant Thornton Advisors LLC (not a licensed CPA firm), which exclusively provides non-attest offerings, including tax and advisory services. 

In January 2025, Grant Thornton Advisors LLC formed a multinational, multidisciplinary platform. The platform offers a premier advisory and tax practice, as well as independent audit practices. With offices across the Americas, Europe and the Middle East, the platform delivers a singular client experience that includes enhanced solutions and capabilities, backed by powerful technologies and a roster of more than 20,000 quality-driven professionals enjoying exceptional career-growth opportunities and a distinctive cross-border culture. 

Grant Thornton is part of the Grant Thornton International Limited network, which provides access to its member firms in more than 150 global markets. 

Grant Thornton LLP, Grant Thornton Advisors LLC and their respective subsidiaries operate as an alternative practice structure (APS). The APS conforms with applicable laws, regulations and professional standards, including those from the American Institute of Certified Public Accountants.

“Grant Thornton” refers to the brand under which the member firms in the Grant Thornton International Ltd (GTIL) network provide services to their clients and/or refers to one or more member firms. Grant Thornton LLP and Grant Thornton Advisors LLC serve as the U.S. member firms of the GTIL network. GTIL and its member firms are not a worldwide partnership and all member firms are separate legal entities. Member firms deliver all services; GTIL does not provide services to clients.

About Grant Thornton Poland

Grant Thornton Poland is one of the leading advisory firms in Poland and is part of the Grant Thornton International Ltd global network. Established in 1993, the firm employs more than 1,200 professionals across seven offices (Poznan, Warsaw, Katowice, Wroclaw, Cracow, Torun, Rzeszow) and serves over 3,000 clients annually, both domestic and international. 

It provides a comprehensive range of services, including audit, tax, legal, and transactional (M&A) advisory, as well as accounting, payroll outsourcing, and digital and cybersecurity consulting. Combining deep expertise, exceptional client service with a flexible approach, Grant Thornton supports mainly medium-sized and large businesses in managing complex projects and strategic transformations. 

Over the past decade, the firm has tripled its headcount and increased its revenues fivefold, growing both organically and through mergers and acquisitions. Grant Thornton is also a market leader in Poland in the field of ESG reporting audits for listed companies, and one of the leading firms providing support for the development of family businesses as well as advisory services in mergers and acquisitions. 

The firm is also actively implementing its sustainability strategy, particularly through initiatives that support local communities, promote economic education and advocate for improving economic legislation.