BDO UK and BDO Ireland have completed their merger to form a single unified entity, BDO LLP, with the combination taking effect on 4 July 2026, aligned with the start of the firms' new financial year, as reported by the International Accounting Bulletin. The merged business generates annual revenue of close to £1.1bn ($1.4bn/approximately €1.28bn), employs approximately 8,500 people and has around 500 partners.

The merger adds BDO Ireland's offices in Dublin and Limerick to BDO UK's existing network of 17 locations. BDO LLP continues as part of BDO International, the global network operating across 169 countries and territories with revenues of around $11bn (approximately €10.1bn) and more than 95,000 people across 870 offices.

Mark Shaw continues as managing partner of the merged entity, with Brian McEnery remaining as regional managing partner for Ireland. The company said it will maintain investment in client service, quality, digital tools and people development.

Shaw said the accountancy profession was transforming to reflect changing client needs and the desire for closer international working, and added: "Bringing BDO UK and BDO Ireland together is our response to that shift, creating greater scale, capability and investment capacity for the future. Today marks an important milestone in that journey and the beginning of the next chapter of our growth story."

McEnery said the merger was built on a foundation of shared culture and mutual respect, and added: "Clients will gain access to a wider network of specialists across the UK and Ireland, while our people will benefit from greater opportunities for collaboration, development and long-term growth. Together, we are building a stronger platform for our clients, our colleagues and our future."

The two practices had worked together on cross-border mandates, shared talent programmes and joint sector projects over many years ahead of the formal combination. The merger positions BDO LLP as a significant competitor in the mid-tier accountancy market across the UK and Ireland at a time when consolidation across the profession is accelerating, driven by private equity investment in rivals and growing demand from clients for integrated cross-border service delivery.