News
Warburg Pincus Announces Partnership with Marissa Thomas and Steve Varley to Launch Unity Advisory, a Next-Generation CFO Advisory Firm Jun 30, 2025
London, June 30, 2025 – Warburg Pincus, the pioneer in private equity global growth investing, has announced a partnership with Marissa Thomas and Steve Varley, two of the UK’s most accomplished professional services leaders, to establish Unity Advisory, a next-generation CFO advisory firm. Unity Advisory will initially provide Office of the CFO services spanning business finance, finance operations, tax and compliance, deal readiness, digital and transformation to private equity-backed and other upper mid-market businesses.
Unity Advisory is financed through an initial equity line of up to $300 million from funds affiliated with Warburg Pincus, along with a substantial additional commitment from the founders. Further capital may be deployed to support future expansion and enhance the value proposition.
The firm sets itself apart by offering Partner-led, high-touch, technology-driven services without the constraints of audit conflicts. From day one, AI will play a central role in how the firm works and serves clients. A key focus of investment will be in AI and cutting-edge automation, which—combined with an experienced and expert team—will help deliver exceptional service, be outcome driven, with client service leaders who are client-focused. Headquartered in London, the firm plans to expand into other key markets and geographies over time.
Marissa Thomas, formerly Managing Partner of PwC UK, founded Unity Advisory and serves as CEO. Steve Varley, formerly EY UK&I Regional Managing Partner and Chair of EY UK, assumes the role of Chairman. David Tapnack joins the team as Managing Partner. Unity Advisory launches with an initial group of experienced partners and team members recruited from the Big Four and other market leading firms. Rapid expansion is anticipated through accelerated hiring of partners and other talent, as well as selective acquisitions.
“We believe there is a more effective way to serve CFOs, and our extensive market research supports this belief,” said Marissa Thomas, CEO of Unity Advisory. “Clients desire senior-level attention, strong technical and industry expertise and a firm that matches their pace. We have assembled a highly experienced team and are committed to building a leading business with strong support from a premier global private equity investor.”
“Unity Advisory offers clients greater choice in CFO services, reflecting a deep understanding of what clients want,” stated Steve Varley, Chairman of Unity Advisory. “Our goal is to create a next generation firm that is entrepreneurial in spirit and rigorous in execution. The business has launched with great momentum; we already have significant client interest which will fuel growth, and a strong recruitment pipeline of talented individuals seeking more variety, reward, and pace in their careers, with a path to Partnership based on an inclusive meritocracy.”
The partnership with Warburg Pincus builds on the firm’s successful and entrepreneurial track record in professional services, including its historical investment in Evelyn Partners’ professional services business and backing the launch of new platforms such as insurance brokerage McGill and Partners.
David Reis, Managing Director, and Rianne Schipper-Kogel, Principal at Warburg Pincus, commented: “We are thrilled to support Marissa, Steve, David and the broader team in the creation of Unity Advisory. Based on our sector experience, we believe the Company will offer a highly distinctive proposition to CFOs and be uniquely positioned to capitalize on what we believe is a substantial market opportunity.”
About Unity Advisory
Unity Advisory is a London-based firm providing Office of the CFO services to private equity-backed and other upper mid-market businesses. With offerings across business finance, finance operations, tax and compliance, deal readiness, digital and transformation, the firm delivers Partner-led, high-touch, technology-driven solutions — free from the constraints of audit conflicts.
From inception, Unity Advisory has embedded AI at the core of its operations and client delivery. Combining deep experience with a forward-looking technology vision, the firm is redefining how CFO functions are supported in today’s fast-moving business environment. With plans to expand into other key markets and geographies, Unity Advisory is poised for growth while remaining committed to excellence, innovation, and client success.
Unity Advisory was founded by Marissa Thomas, formerly Managing Partner of PwC UK, who now serves as CEO. Steve Varley, former EY UK&I Regional Managing Partner and Chair of EY UK, joins as Chairman. David Tapnack takes on the role of Managing Partner. Together, the leadership team brings deep expertise and a bold vision for transforming finance functions through innovation and experience.
For more information, please visit: https://unity-advisory.com/
About Marissa Thomas, Steve Varley and David Tapnack
Marissa Thomas was a partner at PwC for over twenty years, holding a number of leadership roles in the UK partnership. Most recently until June 2024, she was Managing Partner and COO. Marissa is an experienced and well known adviser to the private equity industry. Today, Marissa is a non executive director for ECIT, a professional and technology services business which has a minority investment by funds advised by TowerBrook Capital Partners (U.K.) LLP. Marissa is CEO of Unity Advisory, a next-generation CFO advisory firm, backed by Warburg Pincus.
Steve Varley was a Partner at Andersen Consulting, and then Accenture, before joining EY in 2005. In 2011 he was elected as the UK&I Regional Managing Partner and UK Chair of EY, a role he held for 9 years. Steve's last role at EY was as Global Vice-Chair Sustainability. He left EY at the end of 2023 and now chairs DWF Group, a global law firm and portfolio company of Inflexion, and is Chairman of Unity Advisory, a next-generation CFO advisory firm, backed by Warburg Pincus.
David Tapnack was a partner at PwC for sixteen years, where he founded the firm’s tech-enabled CFO Office and Insight & Analytics business. He subsequently held several senior roles in the UK firm including Head of Commercial, Chief People Officer for Transaction Services, and Chief Operating Officer for Forensics. David has advised private equity investors and their portfolio companies for twenty years. He left PwC in 2024, and is the Managing Partner of Unity Advisory, a next-generation CFO advisory firm, backed by Warburg Pincus.
About Warburg Pincus
Warburg Pincus LLC is the pioneer of private equity global growth investing. A private partnership since 1966, the firm has the flexibility and experience to focus on helping investors and management teams achieve enduring success across market cycles. Today, the firm has more than $87 billion in assets under management, and more than 220 companies in their active portfolio, diversified across stages, sectors, and geographies. Warburg Pincus has invested in more than 1,000 companies across its private equity, real estate, and capital solutions strategies.
The firm is headquartered in New York with offices in Amsterdam, Beijing, Berlin, Hong Kong, Houston, London, Luxembourg, Mumbai, Mauritius, San Francisco, São Paulo, Shanghai, and Singapore. For more information, please visit www.warburgpincus.com or follow us on LinkedIn.
Media Contact:
Alice Gibb
+44 20 730 603 90
alice.gibb@warburgpincus.com