The Manchester-based estate agent reported income growth of 9.5% to £4.5m in 2012 from its combined revenue streams of residential sales, lettings and property management.
Operating profits rose by 44% from £576,089 to £829,025. Residential property sales volumes grew by 15% last year, but 61% of revenue came from residential letting and property management activity. Total rents collected on behalf of landlord clients exceeded £13.5m, a record in the firm's 21 years.
The company said it benefited from investment in software linking prospective buyers and renters with their ideal property.
Thornley Groves operates from 10 sites in Manchester city centre and North Cheshire.
Last year the agent acted on the sale of 750 homes, secured more than 1,600 lettings and managed over 2,000 properties for private landlords.
Michael Groves, managing director of Thornley Groves, said: "We are very pleased with the significant progress made in 2012. Thornley Groves expects to see further revenue growth over the next 12 months.
"With the availability of mortgage finance expected to continue to ease in 2013 together with vendors increasing willingness to accept current market values, understanding that they can also buy for lower prices than expected, we anticipate continued growth in residential sales which will deliver a greater proportion of our total revenue."