AmTrust Financial Services has completed the purchase of Californi-based Builders & Tradesmen's Insurance Services (BTIS), which provides specialty insurance products to their target market of small business customers.

AmTrust CEO Barry Zyskind said that they expect the acquisition of BTIS to add more than $70m in premiums over the next year.

BTIS, headquartered in Rocklin, is an insurance wholesaler and general agent specializing in the procurement and brokering of insurance policies and bonds for small contractors. The company writes business in 12 western states.

AmTrust Financial Services, headquartered in New York, is a multinational insurance offering specialty property and casualty insurance products, including workers compensation, commercial automobile and general liability as well as extended service and warranty coverage