Two Mayo accountancy practices to merge with RBK Chartered Accountants

Two long established Mayo accountancy practices are to merge with Ireland’s largest independent firm of chartered accountants.

As Ireland’s largest independent firm of Chartered Accountants, RBK has merged with MCP Accountants and OMC O’Malley & Company, both long established accountancy practices based in Castlebar, with effect from May 2025.

The combined entities will have revenue of in excess of €26 million, a team of 19 partners with over 270 professionals and support staff across four offices, consolidating RBK’s position as a leading national accountancy and advisory firm. The merged firms will trade as RBK.

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The merger will establish a new RBK office in Castlebar and Cathal Melia, Audit and Business Advisory Partner will act as Partner in Charge and will oversee the integration of the full range of RBK services into the Castlebar Office.

Reflecting on today’s announcement, Joe Cleary, Managing Partner with RBK, said: “This is a significant milestone for our firm and we take great pride in our existing links to the region and in the strong presence we have built in the West of Ireland. This new chapter is a key part of our growth strategy as we continue to position ourselves for future expansion, combining talent and resources to meet the evolving needs of our diverse client base. The mergers with MCP Accountants and OMC O’Malley & Company mark a major step in strengthening our nationwide presence, and we look forward to providing a comprehensive service offering from the enhanced North West base.”

Pearce O’Malley, Managing Partner at OMC O’Malley & Co Chartered Accountants, added: “We are delighted to merge our practice with RBK, joining one of Ireland’s leading accounting firms. We have worked with RBK for the benefit of mutual clients from the very start of our practice in 1985 and see RBK as continuing the ethos of our firm through client personal service. This partnership provides access to extensive expertise and a broad range of professional services, including specialist corporate and private client tax planning, audit, accounting and business advisory solutions. We look forward to enhancing the value we deliver to our clients and the opportunities for our team through this collaboration.”

Michael Cosgrove, Managing Partner at MCP Accountants, commented: “This merger is an excellent fit, both in terms of client focus and cultural alignment, and we are excited to collaborate with and get to know our new colleagues. My fellow partners and I made the decision to merge with RBK because we firmly believe it is in the best interests of our clients and our team. As part of a larger, thriving practice, we can now offer enhanced continuity of service to our clients and significantly improved career opportunities for our team.”