The first pay reference period will be the first time pension contributions are deducted after the employer’s staging date/duties start date or postponed staging date/duties start date.

For example, where the employer’s staging date/duties start date is 1 June, if an employee is paid on 25 June for a calendar monthly payroll, it would be the period beginning 1 June and we would need details of the payment made in that period (i.e. on 25 June).

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See The Pension Regulator   for more information.