The proposed merger between BDO UK and BDO Ireland has moved a step closer, with the two firms exchanging contracts after partners approved the deal.

In a statement, BDO UK said the deal will add BDO Ireland’s offices in Dublin and Limerick to the UK business’ 17 existing locations.

In November 2025, the two companies confirmed that they were in talks to combine operations and said discussions were in their concluding phase.

The transaction is subject to regulatory clearance and is expected to complete in spring 2026.

On completion, the merged business is expected to generate approximately £1.1bn in annual revenue and employ around 8,500 people. The combined business will comprise roughly 550 partners.

BDO UK managing partner Mark Shaw 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.

“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 transaction, an ‘in-network’ merger within the BDO structure, is expected to strengthen BDO’s position as one of Europe’s largest accountancy groups focused on mid-market clients.

The combined entity will expand BDO’s capabilities across its four core service lines – audit, tax, deals and consulting, and risk and outsourcing. It will also strengthen coverage in key growth sectors across the UK and Irish economies.

BDO UK added that the merger is intended to better meet shifting client needs by improving cross-border collaboration and service consistency.

The enlarged organisation will continue to operate within the BDO International network, which reports global revenues of around $11bn, with more than 95,000 people in 870 offices across 169 countries and territories.