Some NHS pensioners may face cuts in their pensions from April after it was discovered some people receiving public sector pensions might have been paid up to twice as much as they should have been.

The error occurred when guaranteed minimum pensions were not taken into account when annual pension increases were calculated.

The NHS Business Services Authority said no overpaid monies paid until 5 April 2009 will have to be paid back but correct rates will be paid from 6 April – the start of the new financial year.

NHS Pensions has written to all those affected and an investigation into the error has been launched. The authority said that as the situation was complex it would take a few months to discover what went wrong. NHS Pensions will write to those affected again when the impact on their pensions becomes clearer.

Anyone who is concerned about the move can contact a dedicated helpline on 0845 610 1115. Calls will be charged at a local rate.