On paper, many accountancy deals look excellent. The real test comes later.

In nearly a decade working in UK accountancy acquisitions and exits, I have seen the same pattern repeat itself. A deal looks commercially sound at the point of agreement. The numbers make sense, both sides feel positive, and the transaction moves forward quickly. Then six to twelve months later, the cracks begin to show. Where deals start to struggle. When acquisitions are built primarily around headline numbers, problems tend to surface once integration begins. Clients do not always transition as expected. Teams resist changes in systems or culture. Earn-outs become areas of contention rather than alignment.

What initially appeared to be a straightforward deal can quickly become a complicated one. The deals that actually work. The strongest acquisitions I have seen were never built around numbers alone. They were built around strategic alignment. The buyer had a clear picture of the type of clients they wanted to grow with. The seller understood the direction the acquiring firm was taking. Both sides shared realistic expectations about how the transition would unfold. When that alignment exists, the deal tends to look just as sensible several years later. Structure and a shared, well communicated vision matters more than price.

One of the most common mistakes in accountancy M&A is focusing heavily on valuation while overlooking the structure behind the deal. Price is visible and easy to debate. Structure is what determines whether the deal holds up once real-world variables appear. Payment schedules, transition periods, client handover processes, and earn-out logic all play a far bigger role in long-term success than many realise.

A transaction is really a transition. An accountancy firm sale is rarely just a financial transaction. It represents the transfer of long-standing client relationships, team dynamics, and a reputation that may have taken decades to build. When the structure reflects that reality, buyers gain confidence in the growth they are acquiring, and sellers can step away knowing their firm will continue in the right hands. The question that reveals everything. Whenever I review a potential deal structure, one question usually reveals whether it has been designed properly. Will this still make sense in three years’ time? If the answer is unclear, the structure normally needs more work. Because the best deals are not simply the ones that complete. They are the ones that still make sense long after completion.