What is a simple assessment from HMRC?
Answered 11 March 2026
What is a Simple Assessment from HMRC?
What the law says
Simple Assessment is a power introduced by section 167 and Schedule 23 of the Finance Act 2016, which inserted section 28H into the Taxes Management Act 1970 (TMA 1970). It applies from the 2016-17 tax year onwards.
Under this power, HMRC can make an assessment of income tax or capital gains tax directly — without requiring the taxpayer to complete a Self Assessment tax return.
A taxpayer who believes a Simple Assessment is or may be incorrect may raise a statutory query under s31AA TMA 1970 within 60 days of the date the notice was issued (or such longer period as HMRC may allow). There is no right of appeal unless and until HMRC has issued a final response to that query.
HMRC guidance / practice
What triggers a Simple Assessment: Simple Assessment was introduced in September 2017 as a method of collecting underpaid PAYE tax following the end-of-year reconciliation, where the underpayment cannot be collected via the individual's tax code. It replaces the previous voluntary payment process and removes the need for affected customers to complete a Self Assessment return.
In practice, a Simple Assessment year occurs when the final result of a PAYE reconciliation is an underpayment that cannot be coded out into a future tax code.
How the taxpayer is notified: Where a reconciled underpaid tax year is to be collected by Simple Assessment, HMRC issues a PA302 — a tax calculation containing details and reasons for the underpayment, a charge reference, and a due date.
Payment due dates:
- If the end-of-year reconciliation is completed between April and 24 October, the due date is 31 January of the following year.
- If completed after 24 October, the due date is 3 months and 7 days from the reconciliation date.
Querying or appealing: If a taxpayer disagrees with a Simple Assessment, they must first raise a query under s31AA TMA 1970. Only once HMRC has issued its final response to that query does the normal appeals process become available.
In summary: A Simple Assessment is HMRC's mechanism for collecting an income tax underpayment (arising from PAYE) by issuing a direct tax calculation (PA302) to the taxpayer, rather than requiring them to file a Self Assessment return — used where the underpayment is too large to be collected through the tax code.
Citation sources
A Simple Assessment year occurs when the final result of a reconciliation or multiple year reconciliation is underpaid and the underpayment cannot be coded. Where the underpaid result cannot be coded the following Simple Assessment process will continue as follows: Voluntary payments and overpayments can only be applied if these fully clear the Simple Assessment underpayment. Any that would only part pay a Simple Assessment will be repaid (see PAYE96310) Any ‘outstanding debts’ for example Self
Where a reconciled underpaid tax year is to be collected by Simple Assessment a PA302 is issued to the customer. The PA302 is a tax calculation and contains a charge reference, a due date and reference to the legislation. The following table shows when a PA302 would be issued Reconciliation Event Output Reconciled-Underpaid. Year cannot be coded, to be collected by Simple assessment (2016-17 onwards) PA302 tax calculation containing details and reasons for the underpayment, charge reference and
Where a customer disagrees with a Simple Assessment there is no right of appeal (and consequently no right of review is available) unless the customer has raised a query under s31AA TMA1970 and been given a final response to that query. If the customer believes that a Simple Assessment is or may be incorrect, then they may raise a query under s31AA TMA1970 within a period of 60 days after the date the notice of Simple Assessment was issued, or such other longer period as HMRC may allow. Upon iss
Where HMRC makes a Simple Assessment of income tax or capital gains tax, if the taxpayer believes that the assessment is or may be incorrect then they may raise a statutory query. Only if they are dissatisfied with HMRC’s final response to their query can they then appeal against their Simple Assessment.
PART 11 Administration, enforcement and supplementary powers Assessment and returns Simple assessments 167 1 Schedule 23 contains provisions about simple assessments by HMRC. 2 Paragraphs 1 to 8 of that Schedule have effect in relation to the 2016-17 tax year and subsequent years. 3 Paragraph 9 of that Schedule comes into force on such day as the Treasury may appoint by regulations made by statutory instrument. 4 Regulations under subsection (3) may— a commence paragraph 9 generally or only for
Simple Assessment was introduced in September 2017, as a method of collecting any underpaid PAYE tax following the End of Year reconciliation, where the underpayment cannot be collected via the individual’s tax code, from tax year 2016-17 onwards. Simple Assessment introduces legislation which replaces the PAYE voluntary payment process and removes the need for customers to complete a Self Assessment tax return, which was the method of enforcing payment of underpaid PAYE tax before Simple Assess