Taxes Management Act 1970 section 30A

Assessing procedure

Section 30A sets out the procedure that applies when HMRC officers make formal tax assessments on taxpayers, as distinct from self-assessments completed by taxpayers themselves.

• All tax assessments that are not self-assessments must be made by an HMRC officer, unless legislation provides otherwise.
• Income tax chargeable under different parts of the employment or trading income legislation can be combined into a single assessment.
• The taxpayer must be sent a notice of assessment stating the date of issue and the deadline for lodging an appeal.
• Once the notice has been served, the assessment cannot be changed except where the tax legislation expressly permits it.