Blick Rothenberg chief executive Nimesh Shah told City AM that the firm “killed” the traditional partnership model a decade ago and now serves as the blueprint that many mid-tier accountancy rivals are trying to follow.

The City-based firm is widely regarded as the first major UK accountancy business to receive private equity backing, after HgCapital invested in July 2016. Shah described that deal to City AM as the firm’s “Super Bowl moment.”

Looking back on the transaction, Shah said many people were “surprised” at the time. But with private equity investment now flowing more heavily into UK accountancy, he said: “You can blame Blick Rothenberg for what’s been happening in the sector for the last 10 years; we started this.”

In recent years, private equity groups have taken stakes in a number of prominent mid-tier accountancy brands, including Apax’s £700m investment in Evelyn Partners and Grant Thornton’s partnership with private equity firm Cinven. Shah said that currently 20% to 30% of UK accounting firms have private equity backing, and an even larger share are open to outside capital when it is offered.

“In accountancy, the partnership [model] is long dead,” Shah said, adding that the sector “clung onto it [too long]… because we don’t like change.”

“If you want to create value and create longevity in a business, then you should be running it like a corporate with proper corporate governance and thinking about the long term, because these businesses should be more long-term.”

Accountancy firms, like much of the professional services industry, have traditionally operated as limited liability partnerships, or LLPs. Under that structure, members known as equity partners put in their own capital, take on the related risk and share profits.

Shah said that model is now being reconsidered because firms need substantial investment for technologies such as AI, and because outside capital can be easier to secure for a firm’s future than persuading older partners to give up some of their profits.

“At some point… [external capital] will be the normal business structure for accountancy firms,” he said.

‘We have made mistakes’

Shah said Blick Rothenberg is now “six, seven times bigger in revenues than what it was 10 years ago, and half of that is inorganic growth.” Companies House data show the firm reported turnover of £83.62m for the financial year ending 30 June 2025, up 9% from £76.72m in 2024.

He also said the firm’s growth path was not without problems. Blick Rothenberg “made a tonne of mistakes on M&A…not the M&A itself, but how we went about it,” Shah said, adding that the firm was “naive about how hard M&A is.”

The firm began its acquisition programme in 2017, a year after HgCapital’s investment, with the purchase of boutique accountancy practice Shelley Stock Hutter. It has since bought Westleton Drake, Hazlems Fenton, Rees Pollock, Greenback Alan and, most recently, The VAT Consultancy.

“We should have done more… on the cultural and people integration,” Shah said. He added that the firm is “really choosy” about the M&A it pursues.

“I’m not going off and spending investor money on M&A just for the sake of revenues and profits, because it can destroy the current business and the target business as well if it’s not culturally integrated in the right way,” he said.

Firms battle for cultural integrity

Shah said concerns remain in the sector about the culture that can come with external investors, even as private equity has become more common.

“You’ve also got to be careful who gets better [who you get as backers]… so we were very choosy about HgCapital; they’re really good investors,” he said.

“We’ve worked really hard to maintain the culture here once we’ve got bigger and whilst we’ve got external investment. That’s a red line for me – that we need to make sure we maintain culture.”

He added that the firm will dismiss clients who mistreat staff.

“We will sack clients if they’re not nice to our people…clients should value what we do… I’m never rude to my builder because he does a great job, so there’s no reason why clients should be rude to us,” Shah said.

Even so, he argued that the sector should adapt. Shah said AI could pose an existential threat, especially to smaller firms, as accountancy firms compete not just on scale but on whether they can fund new technology and change operating models fast enough to keep pace.

“There will be a point pretty soon where one of these startup tech businesses will commoditise the actual accountancy side of accounting… a tech startup is successful at commoditising accounts in a £10-a-month type subscription model where you can just get your accounts and tax done automatically through a bank feed,” he said.