A longtime Ann Arbor-based accounting firm is broadening its reach and adding divisions through a merger with a 650-employee statewide firm.

Wright Griffin Davis and Co. is now a part of the Saginaw-based Rehmann Group, which offers accounting, financial management and business consulting services in three states.

The merger moves WGD and its $6.6 million in annual revenue into part of a $70 million statewide firm that has the resources of the larger network behind it.

“Now there are two major regional powerhouse accounting firms in Ann Arbor,” said Scott Price, managing director of WGD, referring to Plante & Moran in addition to his own company.

WGD was founded in the 1950s and firmly established itself as a large local accounting firm, growing to 45 employees this year.

And while it forged affiliations with various entities to give its customers access to specialties it didn’t have in house - such as various international accounting functions and investigative services - that wasn’t always enough for clients.

“We do find ourselves bumping heads with larger firms,” said WGD partner Rod Byrne. “We wouldn’t win a bid because people (thought we were too small).”

Rehmann, meanwhile, has been expanding geographically - with offices in 10 Michigan markets and 3 each in Ohio and Florida - and creating new divisions. In addition to accounting, it also operates wealth management and corporate investigation divisions.

The company has $2 billion in assets under management and about 40 percent of its growth has come via merges, said CEO Steve Kelly.

“Our model is to find the premier firm in a market,” Kelly said.

For the WGD deal, the companies have been hammering out details of the merger since early summer, though the move has been appealing to both for a number of years, Byrne said.

“We didn’t think we were in a spot where we wanted to do that yet,” he said. “”We got to that point this year.”

It also fit Rehmann’s goals to establish a presence in Ann Arbor, one of the few larger markets in the state - outside of Detroit - where the firm still had no footprint.

The changes are already taking place in the Ann Arbor office. Employees learned of the move in late September, Kelly visited with the leadership team at the end last week.

No staffing changes are planned in the Ann Arbor office, though eventually some employees may be added. Over time, staff also will find new opportunities to specialize.

Meanwhile, on Monday, an all-staff meeting in the Ann Arbor office will roll out more details as the systems of the two companies are merged.

The transaction calls for all of the WGD assets to be moved into the Rehmann Group, and the WGD partners will now have a stake in Rehmann.

The change at WGD speaks to how business in Ann Arbor has changed over the decades, Byrne said.

“A small Ann Arbor business can be doing business in Brazil, Buenos Aires, Paris, wherever,” he said. “We have clients with a lot of global and technology needs.”

Paula Gardner is Business News Director of AnnArbor.com. Contact her at 734-623-2586 or by email. Sign up for the weekly Business Review newsletter, distributed every Thursday, here.