Self-assessment and payment of tax

Self-assessment notification of chargeability: by when must an individual notify HMRC?

By 5 October following the end of the tax year (unless HMRC has already issued a notice to file a return).

Notification of chargeability: what are the maximum penalties for failure to notify (non-deliberate / deliberate / deliberate and concealed)?

30% / 70% / 100% of potential lost revenue (PLR).

Failure-to-notify penalty: when can it be reduced to 0%?

Non-deliberate failure with unprompted disclosure within 12 months.

Exemption from notifying chargeability: which three general conditions must be met before the income tests are considered?

No chargeable gains, not liable to higher rate tax, and all income falls within the listed categories (PAYE, not taxed under SA, taxed at source, or savings/dividend income within the nil rate bands).

SA return filing deadlines: paper vs electronic?

Paper: 31 October following the end of the tax year. Electronic: 31 January following the end of the tax year.

SA return filing date where HMRC issued the notice to file late: what is the deadline?

The later of the normal deadline and three months from the date of the notice.

SA return filing: Gotcha. Notice issued 14 December 2026 for 2025/26, filed electronically. What is the deadline?

13 March 2027 (three months from the notice is later than 31 January 2027).

SA return filing: Gotcha. Notice issued 16 May 2026 for 2025/26, filed electronically. What is the deadline?

31 January 2027 (three months from the notice is earlier).

HMRC to calculate the tax on a paper return: by when must the paper return be filed?

By 31 October Year 2, or within two months of the notice if the notice was issued after 31 August Year 2.

Electronic SA return: who calculates the tax liability?

It is calculated automatically when the return is filed online.

Late filing of an SA return: when does the penalty date fall?

The day after the filing date.

Late filing penalty: initial penalty and when does it apply?

£100, as soon as the return is late (0–3 months), even if there is no tax due.

Late filing penalty, 3–6 months late: what additional penalty applies?

£10 per day, maximum 90 days (£900).

Late filing penalty, 6–12 months late: what additional penalty applies?

The greater of 5% of unpaid tax and £300.

Late filing penalty, 12 months or more late: what additional penalty applies?

The greater of a conduct-based % of unpaid tax and £300.

Late filing penalties: are the stages cumulative or replacements?

Cumulative (they stack on top of the £100).

Penalties for errors in SA returns: what is the penalty base?

Potential lost revenue (PLR), i.e. the extra tax due on the corrected figure (including Class 4 NICs where relevant).

Maximum penalties for errors: careless / deliberate not concealed / deliberate and concealed?

30% / 70% / 100% of PLR.

Minimum penalties for errors with UNPROMPTED disclosure: careless / deliberate not concealed / deliberate and concealed?

0% / 20% / 30%.

Minimum penalties for errors with PROMPTED disclosure: careless / deliberate not concealed / deliberate and concealed?

15% / 35% / 50%.

Error penalties: which other taxes use the same common penalty regime?

Corporation tax returns and VAT returns (as well as SA returns).

Error penalties: where are the percentages found in the exam?

They are given in the Tax Rates and Allowances.

Amendment of an SA return by the taxpayer: what is the time limit?

12 months after the filing date (31 January Year 2, or the last day of the three-month period if the notice was late).

Amendment of an SA return by HMRC: what is the time limit?

Nine months after the day the return was actually filed.

Amendment of an SA return: Gotcha. Which deadline runs from the due filing date and which from the actual filing date?

Taxpayer: 12 months from the due filing date. HMRC: nine months from the actual filing date.

HMRC amendment of an SA return: how long does the taxpayer have to object?

30 days from receiving notice of the correction.

HMRC amendment of an SA return: what may it correct?

Obvious errors or omissions (errors of principle, arithmetical mistakes), or anything else an officer has reason to believe is incorrect in light of the information available.

Record retention for individuals in business: how long?

Five years after the 31 January following the tax year.

Record retention for individuals not in business: how long?

One year after the 31 January following the tax year.

Record retention: who counts as "in business"?

A sole trader, a partner, or someone letting property.

Record retention: Gotcha. For a business owner, does the five-year period apply only to the business records?

No, it applies to ALL records needed for the return (e.g. employment records too).

Record retention: 2025/26 return, taxpayer in business. Until when must records be kept?

31 January 2032.

Maximum penalty for failure to keep and retain records?

£3,000 per tax year.

Payments on account (income tax and Class 4 NIC): what are the two due dates?

31 January during the tax year and 31 July following the end of the tax year.

Payments on account: how much is each payment?

50% of the previous year's relevant amount.

Payments on account: what is the "relevant amount"?

The previous year's income tax and Class 4 NIC payable by self-assessment, excluding amounts deducted at source (e.g. PAYE).

Payments on account: Gotcha. Is tax deducted at source (PAYE, loan stock) deducted from or included in the relevant amount?

Deducted (excluded from it). Class 4 NIC is added.

Payments on account: below what relevant amount are they not required?

Under £1,000.

Payments on account: can they be reduced?

Yes, by claim, if the taxpayer expects the current-year liability to be lower.

Payments on account: is CGT included?

No. POAs cover income tax and Class 4 NIC only.

Payments on account: worked recall. 2024/25 income tax £9,200 (including £1,200 tax at source) and Class 4 NIC £1,900. What is each POA for 2025/26?

(£9,200 − £1,200 + £1,900) = £9,900, then × 50% = £4,950 on 31 January 2026 and £4,950 on 31 July 2026.

Balancing payment: due date?

31 January following the end of the tax year.

CGT payment date for most disposals?

31 January following the end of the tax year.

CGT on residential property: when is the payment on account due?

Within 60 days of completion of the disposal.

Interest on late-paid tax: from when to when does it run?

From the due date until the day before the actual payment date.

Interest on late-paid tax: which payments does it apply to?

Payments on account and balancing payments.

Interest on overpaid tax (repayment supplement): from when to when does it run?

From the original date of payment until the day before the repayment is made.

Repayment supplement: is it taxable for individuals?

No, it is tax free.

Interest rates for the Dec 2026 exam: underpaid tax / overpaid tax?

8.50% / 3.50% (given in the exam; FA version sensitive).

Late-paid tax penalties: which payments do they apply to?

The balancing payment and CGT (not payments on account).

Late-paid tax penalty date?

30 days after the due date.

Late-paid tax penalties: payment made on or before the penalty date?

0%.

Late-paid tax penalties: payment made within 5 months after the penalty date?

5% of the unpaid tax.

Late-paid tax penalties: payment between 5 and 11 months after the penalty date?

10% of the unpaid tax.

Late-paid tax penalties: payment more than 11 months after the penalty date?

15% of the unpaid tax.

Compliance check notice: deadline where the return was filed on or before the filing date?

The first anniversary of the actual filing date.

Compliance check notice: deadline where the return was filed late?

The quarter day following the first anniversary of the actual filing date.

Quarter days for compliance check deadlines?

31 January, 30 April, 31 July, 31 October.

Compliance check deadline: Gotcha. Return filed 28 March 2027 (late). What is the latest notice date?

30 April 2028.

HMRC determination: what is it?

An HMRC assessment of the amounts liable to tax.

HMRC discovery assessment: when is it used?

To recover tax lost, e.g. through a careless or deliberate understatement.

Dishonest conduct of tax agents: maximum HMRC penalty?

£50,000.

Tax appeals: what is the order of process?

Appeal to HMRC, then (optional) internal review by an objective HMRC officer, then the Tax Tribunal.

Late FILING penalty vs late PAYMENT penalty: which is based on lateness of the return and which on the unpaid tax?

Late filing: £100 fixed first, then daily and % stages. Late payment: only a % of unpaid tax, starting after the 30-day penalty date.

Interest vs penalty on late-paid tax: which runs from the original due date?

Interest runs from the due date. The late-payment penalty clock starts from the penalty date (30 days after the due date).

Penalty for ERRORS vs penalty for FAILURE TO NOTIFY: same percentages?

Same maximum percentages of PLR (30%/70%/100%), but different base events (incorrect return vs failure to notify chargeability).