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HMRC internal manual

Enquiry Manual

Introduction: Self Assessment Tax System: Outline

Notify Chargeability

For 1995/96 onwards, every person who is not a company and has not received a tax return is required to notify chargeability within 6 months of the end of the tax year in which liability arises.

From 31 January 2001 a person starting their own business must in addition register for Class 2 NIC within 3 months.

Companies are required to notify chargeability within 12 months of the end of their accounting period.

The Return

Returns for individuals and partnerships and trusts generally have to be sent back by 31 January following the end of the tax year. Under SA it is the taxpayer’s responsibility to self assess even if the taxpayer asks HMRC to calculate the liability.

For companies the last date for filing is generally 12 months from the end of the accounting period.

Records to be Kept

All taxpayers are required to keep such records to enable correct and complete returns to be made, CH11000. These records must be preserved, CH13000.

Payment of Tax

Payments on account, each normally equal to half the income tax and Class 4 NIC liability for the previous tax year, are payable on the half yearly dates

  • 31 January in the year of assessment
  • 31 July after the year of assessment

A final balancing payment where appropriate is payable on the next 31 January, at the same time the return is due.

Any Capital Gains Tax liability is also due on 31 January after the end of the tax year. It is excluded from the calculation of payments on account.

Corporation Tax is due for most companies on the day following the expiry of 9 months from the end of the accounting period. Very large companies make quarterly payments.