How do GMP equalisation adjustments change your pension?
Guaranteed Minimum Pensions accrued between 1978 and 1997 were calculated on terms that differed between men and women, because they mirrored unequal State Pension ages. Courts have held that schemes must equalise for that effect, which for some members means a higher pension and arrears — and for most members means no change at all.
- The period: contracted-out service between 6 April 1978 and 5 April 1997.
- The cause: GMPs were calculated on different terms for men and women.
- The effect: some members receive an uplift and arrears; many receive nothing.
- The timing: schemes are working through it individually, and it can take years.
01 Where the inequality came from
A Guaranteed Minimum Pension is the amount a contracted-out defined benefit scheme had to provide in place of the earnings-related State Pension, for service between April 1978 and April 1997. Its calculation mirrored the State Pension rules of the time, which had different ages for men and women.
The result is that a man and a woman with identical service and earnings can have differently shaped benefits — different accrual, different payment ages, and different increases in payment. That inequality is baked into the GMP rather than into the scheme's own rules.
Courts have held that schemes must equalise for the effect, and schemes have been working through the exercise since. It applies to that period of service only; benefits before 1978 and after 1997 are unaffected.
Source: Pension types and how they work
02 What members actually see
For most members the answer is nothing. Equalisation compares the benefits payable to a member against those payable to a comparator of the opposite sex and pays the better of the two, so a member who was already receiving the more favourable treatment sees no change.
For those who were not, the result is an uplift to the pension and arrears for past underpayments, sometimes with interest. The amounts vary enormously between members and between schemes, and small adjustments are far more common than large ones.
Schemes handle the calculation individually and the exercise is administratively heavy, which is why it has taken years. A member cannot accelerate it and does not need to apply.
Shows: the cumulative arrears from a small annual uplift applied retrospectively. Ignores: interest on arrears, tax in the year of receipt, and whether any uplift applies to you at all.
On the defaults above, the worked example shows £1,620. A £180 a year uplift over 9 years is £1,620 of arrears, plus the higher pension continuing.
Source: Pensions Tax Manual
03 What to do about it
Nothing, other than keeping the scheme informed of your address so any adjustment reaches you. There is no application process, no deadline for members, and no advantage in contacting the scheme repeatedly.
Where a transfer is being considered, it is worth asking whether the transfer value has been adjusted for equalisation, because a value calculated before the exercise may not reflect it. A transfer value that predates the scheme's equalisation work is a question to raise rather than an obstacle.
And where a pension has already been in payment for years, an uplift can bring arrears with tax consequences in the year of receipt, so a large adjustment is worth mentioning to whoever prepares your tax return.
Source: Transferring your pension
This is one of the few pension stories where the honest headline is that most people get nothing. Equalisation pays the better of two calculations, so a member who was already on the more favourable side sees no change at all — and of those who do get an uplift, small adjustments are far more common than large ones. There is nothing to apply for and no deadline. The only two things worth doing are keeping your address current with the scheme, and, if you are considering a transfer, asking whether the value has been adjusted for equalisation yet.
FAQ
Which service does GMP equalisation affect?
Contracted-out service between 6 April 1978 and 5 April 1997. Benefits accrued before or after that window are not affected by the exercise.
Will I get an uplift?
Most members will not. Equalisation pays the better of the member's own benefits and those of a comparator of the opposite sex, so anyone already receiving the more favourable treatment sees no change.
Do I need to apply?
No. Schemes are working through the exercise themselves and there is no member application or deadline. The one useful step is keeping your address current so any adjustment reaches you.
Sources
Regulator references
- Pension types and how they work · GOV.UK · 2025The defined benefit and defined contribution split this post turns on.Last verified: 2026-09-07
- Pensions Tax Manual · HM Revenue and Customs · 2025HMRC's own statement of the rule, for the detail the guidance pages compress.Last verified: 2026-09-07
- Transferring your pension · GOV.UK · 2025The transfer rules, including the advice requirement on safeguarded benefits.Last verified: 2026-09-07
Calculator unit tests · the assertions this page's worked example is checked against, and their last result
Changelog
- 2026-09-07 — initial publish (new format)
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Jordan Reeves
Founder of Talk Through Wealth. A software engineer for over a decade before turning to retirement planning, Jordan built the projection engine after watching family members get fragmented, country-by-country advice that never reconciled. He writes about retirement the way the engine computes it: month-by-month, lifetime-long, and skeptical of any rule of thumb that hasn't been run through the math.