The Pensions Board has said that many defined benefit schemes that are in deficit must submit proposals to tackle the deficit by the end of the year.
The deadline forms part of a revised set of rules for defined benefit schemes.
The new rules set out how defined benefit schemes must meet their funding obligations and what steps they must take if they do not.
Defined benefit schemes guarantee a return to individuals which isn't dependent on the contribution paid in by that individual.
Defined contribution schemes only give a return to individuals based on the money they have paid in to scheme.
The full set of rules is published on the Pension Board's website.
These rules follow recent changes to the Pensions Act 1990, as amended, which were introduced on enactment of the Social Welfare and Pensions Act 2012.
The key changes contained in the new rules are that schemes will normally be allowed until 2023 to clear existing deficits, that a risk reserve will be required with effect from 1 January 2016.
Where schemes hold sovereign annuities or sovereign bonds they will be allowed credit for these in their funding standard calculations.
Many defined benefit schemes are in deficit and in a number of cases, the deficit is substantial. The Pensions Board has published deadlines by which these schemes must submit funding proposals to tackle these deficits. The first of these deadlines falls on 31 December 2012.
Brendan Kennedy, Chief Executive of The Pensions Board stated today: "We have today published all the information that scheme trustees and their advisers need to prepare funding proposals to deal with scheme deficits. It is now up to trustees to familiarise themselves with their obligations, and to prepare and submit proposals which will put the finances of their scheme on a long-term stable footing."