§ The Earl of Kimberleyasked Her Majesty's Government:
Whether, when changes in tax regimes are announced in a budget, it is normal practice to give them effect from Budget Day or from 6th April.
The Earl of CaithnessCommencement dates for tax changes announced in the budget depend on the facts and circumstances of each case. For example, it is customary for changes to income tax, particularly to the rates and allowances, to take effect on 6th April, the start of the fiscal year; and changes to corporation tax normally take effect on 1st April, the start of the financial year. However, other days, including Budget Day itself and the day on which the Finance Bill receives Royal Assent, are also frequently used as commencement dates.