The merger of housing finance major HDFC with the country's largest private lender HDFC Bank will be effective from July 1, HDFC Chairman Deepak Parekh said today. The boards of HDFC and the private bank will meet on June 30 post to clear and approve the merger, Parekh told reporters here. The merger of the corporation with HDFC Bank will be effective July 1, Mr Parekh said.