Terms of the transaction, set to close May 1, were not disclosed.

The deal will expand Denver-based IMA’s brokerage services to California, and the combined company will have 1,200 employees and generate annualized revenue of over $300 million, IMA said. Bolton will retain its brand and continue to operate out of its offices in Los Angeles, Orange County and the San Francisco Bay Area.

Bolton is the 59th largest broker of U.S. business, with $54.86 million in 2019 U.S. brokerage revenue, according to Business Insurance’s latest rankings. IMA is the 28th largest broker of U.S. business, with $175.86 million in U.S. brokerage revenue in 2019, based on the same rankings.

The deal follows IMA’s acquisition of Springfield, Oregon-based k.p.d. Insurance Inc. earlier this month.

Bolton will expand IMA’s geographic reach and employee benefits business, IMA Chairman and CEO Rob Cohen said in an interview with Business Insurance.

Employee benefits revenue will account for $64.1 million, or about 21%, of the combined business, based on the latest figures, Mr. Cohen said.

Bolton will strengthen IMA’s specialties business, adding expertise in education and expanding its capabilities in construction, he said.

Both companies are “fiercely committed to independence and private ownership. We decided it makes sense for us to join forces and focus on building the broker of the future,” Mr. Cohen said.

Bolton President and CEO Steve Brockmeyer will serve as market president for IMA’s California division, continuing in his leadership role, and Bolton’s 200 employees will join IMA under the deal, he said.

Bolton, which was founded as a family-owned business in 1931, will be the 10th and largest brokerage to be acquired by IMA since early 2020.

“If you look at the top brokers in the industry, you see public firms, you see private equity-backed firms, and you see one large family-owned firm, but what you don’t see is an independent employee-owned firm,” Mr. Cohen said.

IMA’s goal is to continue to grow organically and then “add strategic partnerships when it makes sense,” he said.