The agency rates lenders and servicers of loans on a scale of one to four, with one being the highest.
Ron McCormick, chairman of HML, said: "We are delighted to receive this recognition from Fitch, which provides a strong endorsement of our long-term commitment to efficient client service, investment in technology and extensive experience in the industry over 14 years."
"It is disappointing that the new market entrants have not felt confident enough to subject themselves to such a rigorous review. Perhaps this reflects the difficulty some are experiencing in meeting the requirements in the complex UK market."
