Late Filing & Late Payment Penalties — What Trades Pay HMRC for Missing Deadlines (2026)

Self Assessment Late Filing Penalties

If you're a sole trader or in a partnership, you file a Self Assessment tax return each year. The online filing deadline is 31 January following the end of the tax year (so the 2025/26 return is due by 31 January 2027). Miss it, and the penalties follow a fixed ladder — and crucially, the first penalty applies even if you owe no tax at all.

The filing penalty ladder works like this:

• 1 day late: an automatic £100 penalty, regardless of whether you owe tax or are due a refund.
• 3 months late: £10 for each additional day, up to 90 days — a maximum of £900, on top of the £100.
• 6 months late: a further penalty of the greater of £300 or 5% of the tax due.
• 12 months late: another £300 or 5% of the tax due. In serious cases where HMRC decides the delay was deliberate, this can rise to 70% or even 100% of the tax owed.

At the extreme, a return filed over a year late with tax outstanding can attract more than £1,600 in filing penalties alone — before you add any late payment charges or interest. The first £100 is the one that catches most trades out, because it lands the moment the deadline passes.

Self Assessment Filing Penalty Timeline

Self Assessment Late Payment Penalties

Filing your return is only half the job — you also have to pay the tax. The balancing payment for Self Assessment is due by 31 January too. Late payment penalties are completely separate from late filing penalties, and they run on their own timetable:

• Interest from 1 February: HMRC charges interest on any unpaid tax from the day after the deadline. It accrues daily until you pay.
• 30 days late: a surcharge of 5% of the tax that's still unpaid.
• 6 months late: a further 5% of the tax still outstanding.
• 12 months late: another 5% of the tax still outstanding.

So leaving a tax bill unpaid for a full year adds 15% in surcharges, plus daily interest the whole time. HMRC's late payment interest rate is pegged to the Bank of England base rate plus a margin, so it moves whenever the base rate changes. Check the current rate on GOV.UK rather than assuming — it has been comfortably above the base rate in recent years and is not trivial.

Don't Forget Payments on Account

Many trades are caught out by payments on account — advance instalments towards next year's tax bill that HMRC requires once your liability passes a certain level. You make two: one due 31 January (alongside your balancing payment) and one due 31 July.

The July payment is easy to miss because there's no return to file at the same time — it's a payment-only deadline. Miss it and interest starts running just as it does on the January balance. Budget for both instalments, and remember that in your first year of higher earnings the 31 January bill can effectively be 150% of your actual tax, because you're paying the year's tax plus the first instalment for the next year.

VAT: Late Submission Penalty Points

If you're VAT registered, the penalty regime works differently — it's a points-based system designed to penalise repeat offenders rather than one-off slips. Every time you submit a VAT return late, you get one penalty point. Once you reach the points threshold for your filing frequency, you're charged a fixed £200 penalty, and a further £200 for every late return after that.

The threshold depends on how often you file:

• Quarterly returns: threshold of 4 points.
• Monthly returns: threshold of 5 points.
• Annual returns: threshold of 2 points.

Points expire after a period of good compliance, but if you're at the threshold you'll need to submit a run of returns on time before they reset. The system applies even to nil and repayment returns, so a return with nothing to pay still has to be filed on time.

VAT: Late Payment Penalties and Interest

Paying your VAT late triggers a separate set of charges based on how many days the payment is overdue:

• Up to 15 days late: no late payment penalty, provided you pay in full or agree a Time to Pay arrangement within that window.
• Day 15 to day 30: a first penalty of 2% of the VAT outstanding at day 15.
• Day 30: the first penalty rises — broadly a further 2% calculated on the amount outstanding at day 30, taking the combined first penalty to around 4% for tax still unpaid at that point.
• Day 31 onwards: a second penalty accrues as a daily rate (an annualised percentage of the outstanding balance) until the bill is cleared.

On top of the penalties, late payment interest runs from the due date until you pay, at the base-rate-plus-margin rate. The 15-day grace period makes a real difference: if cash flow is tight, paying or arranging Time to Pay within 15 days of the deadline avoids the penalty entirely, even though interest still applies.

Corporation Tax Late Filing Penalties

If you run a limited company, you have an extra layer of deadlines. Your Company Tax Return (CT600) must normally be filed within 12 months of the end of your accounting period. Filing late attracts:

• 1 day late: £100.
• 3 months late: a further £100.
• 6 months late: HMRC estimates your bill and adds a penalty of 10% of the unpaid tax.
• 12 months late: another 10% of any unpaid tax (so 20% in total once you pass a year).

If your return is late three times in a row, the two £100 fixed penalties each increase to £500. Note that Corporation Tax itself is usually due 9 months and one day after your accounting period ends — earlier than the filing deadline — so paying late and filing late are again two distinct issues, each with their own interest and charges.

Companies House Late Accounts Penalties

Limited companies also file annual accounts with Companies House, and these penalties are entirely separate from HMRC's — you can be fined by both for the same year. For a private limited company, the late filing penalty is charged on a sliding scale depending on how overdue the accounts are:

If you file late two years running, these penalties are doubled. Public companies face higher amounts. The Companies House penalty is automatic and applies regardless of whether your company traded or made any profit, so even a dormant company must file its accounts on time.

Reasonable Excuse and Appeals

You can appeal a penalty if you have a reasonable excuse — something genuinely outside your control that stopped you meeting the deadline. HMRC and Companies House both accept appeals, but the bar is meaningful and not every excuse qualifies.

Examples HMRC has generally accepted include a serious illness or bereavement around the deadline, a fire or flood that destroyed your records, an unexpected hospital stay, or a prolonged failure of HMRC's own online service. Excuses that are routinely rejected include finding the system too difficult, not receiving a reminder, relying on someone else who let you down, or simply not having the money to pay.

If you have a valid reason, appeal promptly — usually within 30 days of the penalty notice — and keep evidence (dates, correspondence, medical letters). Once the excuse ends, you must put things right without unreasonable delay, or the appeal can fail.

How to Avoid Penalties Altogether

Penalties are almost always preventable. A handful of habits will keep you clear of every deadline above:

• File early, not on the deadline. Aim to submit your Self Assessment in the autumn, not on 31 January. Filing early doesn't bring your payment forward, but it removes the filing risk and tells you exactly what you owe with months to plan.
• Budget for tax as you earn. Set aside a percentage of every invoice into a separate savings account — many trades use 25–30% to cover Income Tax, National Insurance and VAT. The money is then ready when the bill lands.
• Use a Time to Pay arrangement. If you genuinely can't pay on time, contact HMRC before the deadline and ask to spread the cost. Agreeing Time to Pay early can stop late payment penalties from being charged, though interest usually still applies.
• Use accounting software and stay MTD-ready. Making Tax Digital requires VAT-registered businesses to keep digital records and file through compatible software, with Income Tax following for many sole traders. Software that tracks deadlines and prepares returns removes most of the manual risk.
• Diarise every deadline. 31 January, 31 July, your VAT return dates, your Corporation Tax dates and your Companies House accounts date — put them all in a calendar with reminders weeks ahead.

The Bottom Line

HMRC penalties are designed to be automatic and unforgiving — but they only catch you if you let a deadline slip. The expensive scenario is a trade who files late and pays late, picking up filing penalties, payment surcharges and daily interest all at once. Keep your records clean, file ahead of time, ring-fence your tax money, and talk to HMRC early if cash is tight. Do that and the penalty ladder simply never applies to you.

Remember that rates, thresholds and deadlines change from year to year. Treat the figures here as a guide and verify the current numbers on GOV.UK or with your accountant before acting on them.