Reading Time | 2 mins 9th December 2025

Yorkshire powerhouse BHP agrees to join Sumer Group in one of the biggest accountancy sector deals of 2025

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Sumer has agreed a landmark deal with BHP, one of Yorkshire’s most respected and fastest-growing accountancy and advisory firms. As the largest independent practice to join a national group in 2025, BHP brings its 150-year heritage into Sumer, more than 420 colleagues and 5 offices across Sheffield, Leeds, York, Cleckheaton and Chesterfield.

BHP brings exceptional regional scale, deep sector expertise and a reputation for straight-talking, relationship-driven advice. The firm has earned its position as one of the North’s leading practices, trusted by thousands of SME and mid-market clients to support their growth, ambition and resilience.

BHP offers a comprehensive suite of services spanning assurance, advisory, tax and corporate finance. Its leadership team will remain in place to continue delivering the recently set out five-year strategy.. By joining Sumer, the firm gains a stronger platform to deliver its £100m ambition while preserving what makes it trusted across Yorkshire.

For Sumer, the agreement to welcome BHP represents a major strategic milestone. The partnership expands the group’s footprint across Yorkshire, strengthens its national corporate finance capabilities, and brings another values-led firm that blends entrepreneurial energy with the depth of expertise clients rely on. A defining moment in Sumer’s mission to champion SMEs across the country.

It also underscores Sumer’s rapid rise as a major new force in the mid-market. Having integrated 41 firms across the UK, Sumer now has more than 65 offices and over 3,000 colleagues. With 15 of those deals agreed in 2025 alone, Sumer is a group built on collaboration, shared values and a commitment to doing the right things for the right reasons.

Warren Mead, Chief Executive Officer of Sumer, said:

“This is a standout moment for Sumer and a brilliant way to finish the year. BHP is a powerhouse in Yorkshire with a long track record of helping businesses thrive. Their culture, ambition and commitment to quality make them an exceptional fit for us. Lisa, Hamish and the team have built something very special. A firm that truly champions its clients and communities. We’re delighted to welcome them and incredibly excited about what we can achieve together for SMEs across the region and beyond.”

Lisa Leighton, Joint Managing Partner at BHP, commented:

“Joining Sumer marks a bold new chapter for BHP. Our five-year plan sets out ambitious goals for growth and innovation, and partnering with a Group that shares our values and drive gives us the platform to accelerate that journey.”

Hamish Morrison, Joint Managing Partner at BHP, continued:

“Maintaining our cultural DNA was vital in finding a partner who can support our growth ambitions. This move expands what we can offer our clients and creates new opportunities for our colleagues across Yorkshire. We’re proud to become part of Sumer and look forward to shaping our future together.”

About Sumer

Sumer is the UK and Ireland’s leading mid-market accountancy practice delivering professional support to small and medium-sized enterprises (SMEs) across England, Scotland and Northern Ireland. A top 15 UK practice, Sumer is on a mission to champion SME businesses and offer local delivery supported by national expertise.

Since its inception, Sumer has grown rapidly through acquisition and organic growth. It now employs more than 3,000 champions, across more than 60 offices, and generates annual revenues exceeding £265 million.

Sumer’s strategy focuses on partnering only with leading regional practices that share the same ethos, values and approach. The Group includes Carpenter Box, Cowgills, DPC Accountants, EQ Chartered Accountants, HW Fisher, Jerroms, Monahans, RMT Accountants & Business Advisors, R.T. Marke & Co Ltd, Scrutton Bland, Simmons Gainsford Group, Sumer Northern Ireland and now BHP.