BDO UK and BDO Ireland have exchanged contracts after partners approved their proposed merger, marking a significant step towards creating one of Europe's largest accountancy groups. The combined business is expected to generate approximately £1.1 billion (€1.27 billion) in annual revenue and employ around 8,500 people across 550 partners.

International Accounting Bulletin reported that the deal will add BDO Ireland's offices in Dublin and Limerick to BDO UK's 17 existing locations.

The two firms confirmed merger discussions in November 2025, stating talks were in their concluding phase. The transaction, subject to regulatory clearance, is expected to complete in spring 2026.

Mark Shaw, managing partner of BDO UK, said: "Partners in both the UK and Ireland have been clear in their support. They are excited about the next phase of our growth story and are pleased to have reached this important stage in the deal."

He added: "This is a merger built on a foundation of shared culture, with mutual respect and commitment to our people, to quality and the consistency of service which our client heartland of entrepreneurial, growing and ambitious businesses requires. We look forward to working, thriving and winning together."

The in-network merger strengthens BDO's position as a major European accountancy group focused on mid-market clients. The combined entity will expand capabilities across audit, tax, deals and consulting, and risk and outsourcing, whilst strengthening coverage in key growth sectors across UK and Irish economies.

The enlarged organisation will continue operating within the BDO International network, which reports global revenues of around $11 billion (€10.1 billion), with more than 95,000 people in 870 offices across 169 countries and territories.

Follow the full details of the BDO UK and Ireland merger and its implications for cross-border professional services delivery.