Jelf Group has bought Brian D Thomas Insurance Services although no financial details of the deal were disclosed.
The corporate services company said following the acquisition, the enlarged Jelf Group's premium income is expected to be over £85m.
The company said Brian D Thomas has a premium income over £9m.
Alex Alway, group chief executive said: "This acquisition offers the group significant opportunities to cross-sell our full range of services whilst enhancing margins as a result of the enlarged group's buying power."