Oaktree has snapped-up the firm from Lloyds Banking Group and the original owners the Cherry family.
The investment giant said the deal would “result in a significant capital injection” including new five-year committed debt facilities of £165m from Lloyds.
Andrew Carr-Locke, Chairman of Countryside Properties, said: “Oaktree is one of the world’s leading investment firms and we’re delighted with their confidence and excitement in the future prospects of Countryside Properties.
“Our strengthened balance sheet will provide a solid base to support the growth of the business. We are also pleased to continue our longstanding relationship with Lloyds Bank Commercial Banking as an ongoing lender.”
Pedro Urquidi, Head of Europe for Oaktree’s Opportunities funds, said: “We are delighted to be acquiring one of the largest privately owned home builders in the United Kingdom.
“We are particularly impressed by Countryside’s high quality south east and east focused land bank as well as its award winning homes and communities.
“We look forward to working with the current management team to continue to optimize, invest in and grow the overall business over time.”