The Pension Schemes Office is an agency of the Inland Revenue. Its main aim is to make sure pension schemes are operating within tax law.
Effectively, it administers pension schemes to ensure they all comply with the tax rules and regulations governing them - they receive generous tax breaks on offer. The PSO gives guidance to life companies and other pension scheme providers on the policies they sell or intend to sell.
If you, as an individual, have a tax query regarding your pension scheme, they should be able to help.