If your pension funds are left in the UK, they could be:
subject to income tax at source of up to 45% when income is withdrawn from the pension. subject to ongoing tax and pension legislation changes. held in £GBP, creating a potential future currency risk. held in an underfunded Defined Benefit Scheme*. held in a scheme giving you no control of the underlying investments. restricted in terms of their growth options and capital protection. held in a scheme which doesn’t allow your family to benefit fully from your pension funds after your death.
* As at July 2023 nearly one in ten of all UK final salary schemes are underfunded, with an aggregate deficit of £2.3bn – Source: UK Pension Protection Fund [PPF].