Most people withdrawing money from their pension funds (over the 25% of the fund that can be taken tax-free) are paying the emergency tax rate, because HMRC will accept only a P45 form as the basis for applying a tax rate to the withdrawal.
That also meant people would have to wait until the end of the tax year before being able to reclaim overpaid tax. But now HMRC has introduced a system for much faster tax reclaims, which it says will allow for repayments within 30 working days. Applicants have to provide details of their income which enables HMRC to work out the correct tax rate.