The UK market for pensions buyouts - the transfer of companies' retirement bills to specialist insurers - has stayed flat over the past year despite the entrance of at least seven new players, including some of the largest investment banks in Europe.

Pensions consultancy Aon, in its first survey of the sector, found that in the first and second quarters of this year a total 125 buyout deals were done, giving a quarterly average of 63 - well below the 84 deals done in the average three-month period last year.