Quentin Marks, located in Bourne, will continue to operate under the same brand name, while director Quentin Rigby will remain with the firm.
The Sharman Quinney Group, which includes Pattison Lane in Kettering and Desborough, Hurfords in Peterborough, Stamford and Uppingham and Kevin Henry in Saffron Walden, Essex, now has 23 branches, with nine lettings centres under five brands.
The new Bourne branch will compliment the Connells Group’s wider offering in Lincolnshire.
Mike Sharman, executive chairman of Sharman Quinney, said: “Quentin Marks is a highly respected business and we’re very pleased to announce this acquisition.
“Quentin has a vast amount of agency experience and has built a fantastic reputation in Bourne and we look forward to creating more opportunities together.
“The brand offers organic growth opportunities, and we will be looking to expand the business, investing our services for lettings, mortgage services and home conveyancing.”
He added: “I am delighted to be joining the Sharman Quinney Group, a business I have admired and respected for a long time. Its wide range of services will help my business to grow even more and working with such a large network of offices will help to cement my strong foothold in the Bourne market.”