I'm guessing that your scheme is a Defined Benefits one, based on the termoinology used so far.
In fact, the Trustees of such a scheme have relative freedom over how they define "pensionable salary". It doesn't have to reflect actual salary.
As ClubMan says, a popular option under such schemes is to reduce the actual salary by some multiple of the State Pension. The thinking is that you will (hopefully) be in receipt of State Pension as well as scheme pension when you retire, so they're targetting getting you a pension of X% of your final salary including the State's offering.
If the scheme permits Additional Voluntary Contributions (AVCs) you can always top up your main scheme benefits with AVCs to a percentage of your actual final salary.
Liam D Ferguson
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