HaysMac acquires Green Square to expand corporate finance advisory

What's the deal? HaysMac, the London-headquartered accountancy, tax, and advisory firm, has acquired Green SquareDealroom has a profile for this one. Try Dealroom →, a specialist corporate finance advisory firm known for M&A advice to founders, management teams, and shareholders. The deal adds 13 staff to HaysMac's UK operations.

Green Square brings more than 20 years of experience advising on transactions across founder-led and investor-backed businesses, with particular strength in marketing, media, and technology sectors.

Why now? HaysMac is marking its 25th anniversary and pursuing an aggressive acquisition strategy. Earlier in 2026, it expanded into the US by acquiring Moore DM's tax team to bolster cross-border services for entrepreneurs and high-net-worth individuals. The Green Square deal continues that momentum.

"Green Square has an outstanding reputation for supporting owners and shareholders through complex, high-value transactions, and their expertise perfectly complements our existing strength in advising growth-focused and investor-backed businesses," said Natasha Frangos, managing partner at HaysMac.

The signal: Mid-market professional services firms are racing to consolidate, snapping up specialist advisory boutiques to offer clients end-to-end support across tax, audit, and M&A. HaysMac's back-to-back acquisitions — first a US tax team, now a corporate finance adviser — illustrate how mid-sized firms are building cross-border, multi-disciplinary platforms to compete with larger rivals for founder-led and investor-backed business.

Read more: consultancy.uk