Northern Gas Networks Pension Scheme, Leeds, England, completed a £385 million ($512 million) buy-in with Legal & General Assurance Society.
The deal covers more than 600 retirees — about two-thirds of its participants, a news release said.
The deal is the first pension risk transfer for the pension fund, which had £464 million in assets as of March 31, said John Baines, partner at Aon, which acted as broker for the deal.
The pension fund is an existing client of Legal & General's money management arm, Legal & General Investment Management, which has run a portion of plan assets since the pension scheme was established in 2005.
"This transaction demonstrates the initiatives and efforts which continue to be undertaken by NGN to manage our commitment to the scheme, balancing the interests of our customers, shareholders and scheme members," David Waite, finance director for NGN, said in the release.