The retirement specialist's defined benefit de-risking business, or bulk annuity sales, rose more than quadrupled to 103.6 million pounds in the three months to Sept. 30. Total sales rose to 359.9 million pounds.

Partnership Assurance, which is being acquired by Just Retirement, said separately that total sales rose 22 percent to 109 million pounds in the third quarter ended Sept. 30. DB bulk annuity new business was 24 million pounds in the quarter.

Partnership Assurance said it was on track to achieve full-year bulk annuity sales of at least 200 million pounds.

Just Retirement agreed to buy Partnership Assurance for 669 million pounds in shares in August, hoping greater scale and a stronger capital position will help it cope with changes that have rocked its industry.

(Reporting by Roshni Menon and Noor Zainab Hussain in Bengaluru; Editing by Gopakumar Warrier)