1 April

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  Payment of corporation tax liabilities for small/medium-sized companies account period ended 30 June 2012.
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  Reduction in main rate of corporation tax to 23%.
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  Change to emission thresholds for business cars.
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  Reclaim 2011/12 Class 1 NICs paid incorrectly because income has been recategorised as self-employment.
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  Application to defer Class 2 or 4 NICs for 2011/12 or claim exception for 2012/13.
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  Multiple contractors to advise HMRC that they wish to be treated as a single contractor for 2013/14.
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  Aggregates levy …