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Self Assessment · standard late filing penalties

HMRC Late Filing Penalty Calculator

Estimate the penalty for filing an individual Self Assessment tax return after its statutory deadline.

The calculation separates the initial £100 charge, daily penalties and the further amounts that can arise after six and twelve months. Late-payment penalties and interest are not included.

Return coveredindividual Self Assessment
Filing methodsonline and paper
Tax yearsgenerated automatically
Rules reviewed5 September 2026

Late return estimate

Calculate a Self Assessment late filing penalty

Choose the tax year and filing method, then enter when the return was filed—or the date to calculate up to if it is still outstanding.

01
Return detailsOne individual tax return
The list updates automatically as tax years end.
The normal online and paper deadlines differ.

Filing position

Use only where HMRC has given a different statutory deadline. Otherwise leave blank.

Tax liability for the late return

£
Use the liability relevant to the late-filing calculation, not the unpaid balance. If it is unknown, enter 0; the six- and twelve-month minimums will still be shown.
02
Estimated late filing penaltySelected tax year
Total standard late filing penalty£0.00Calculated to the date entered
Normal or entered deadline
—
Filed / calculated to
—
Calendar days late
0 days
Tax liability entered
£0.00
Initial fixed penalty
£0.00
Daily penalties
£0.00
0 chargeable days
Six-month further penalty
£0.00
Twelve-month further penalty
£0.00
No late filing penalty at this date

The return deadline has not passed, or the return was filed by the deadline.

Dates used
  • Penalty date: —
  • Daily penalties begin: —
  • Six-month stage: —
  • Twelve-month stage: —

Estimate only. This does not include late-payment penalties, interest, failure-to-notify penalties, partnership penalties, offshore matters or higher penalties for deliberate or concealed withholding.

Direct answer

How much is the HMRC late filing penalty?

An individual Self Assessment return filed after its deadline normally starts with a £100 penalty, even where there is no tax to pay. Once the return remains outstanding for more than three months, daily penalties can add £10 a day for up to 90 days.

At six months, a further penalty is normally the greater of £300 and 5% of the tax liability. In a standard non-deliberate case, the same test applies again at twelve months. More serious twelve-month penalties can apply where information was withheld deliberately or concealed; those require a case-specific review and are not estimated here.

Check Self Assessment penalties on GOV.UK →

Calculation method

The four standard late filing penalty stages

The dates run from the penalty date, which is the day after the filing deadline.

01

Initial £100 penalty

The fixed penalty arises when a required return is filed after the deadline. It does not depend on the amount of tax due.

02

Daily penalties

After three months, £10 a day can apply for up to 90 days, producing a maximum daily total of £900.

03

Six-month penalty

The additional amount is the greater of £300 and 5% of the tax liability that would have been shown in the return.

04

Twelve-month penalty

For a standard non-deliberate failure, another greater-of-£300-or-5% calculation applies. Deliberate cases have different percentages.

Standard individual Self Assessment late filing stages
StageStandard amount used hereMaximum at that stage
Return filed after deadline£100 fixed penalty£100
Outstanding after 3 months£10 per day£900
Outstanding after 6 months5% of liability or £300, whichever is greaterNo fixed maximum
Outstanding after 12 months5% of liability or £300 in a non-deliberate caseHigher rules may apply

Official detail: HMRC late filing penalty stages.

Keep the charges separate

Late filing is not the same as late payment

A person can have a late filing penalty because the return was submitted late and a separate late-payment charge because tax remained unpaid. Interest can also run on unpaid tax. This calculator covers only the standard return-filing failure.

Making Tax Digital: taxpayers within Making Tax Digital for Income Tax can enter the points-based late-submission regime from the tax year they join. This calculator does not estimate that separate regime. See HMRC’s Making Tax Digital penalty rules.

Included here

  • one individual Self Assessment return;
  • normal online or paper deadline;
  • a different deadline entered from an HMRC notice;
  • standard £100 and daily penalties;
  • standard six- and twelve-month additions.

Needs separate review

  • late-payment penalties and interest;
  • failure to notify HMRC;
  • partnership-return penalties;
  • offshore tax matters;
  • deliberate or concealed withholding;
  • reasonable-excuse appeals.

Common questions

HMRC late filing penalty questions

Is there a late filing penalty when no tax is due?

Yes. The initial £100 penalty can apply even when there is no tax to pay. Daily penalties and the £300 minimum amounts at the later stages can also apply where the conditions are met.

What is the difference between late filing and late payment?

Late filing concerns when the return reaches HMRC. Late payment concerns when the tax is paid. A taxpayer may face both sets of charges, and interest may be added to unpaid tax.

Can I appeal a Self Assessment late filing penalty?

A penalty can be appealed where there is a reasonable excuse or another valid basis. Keep evidence, file the outstanding return promptly and follow the deadline and instructions on the penalty notice. Check the official Self Assessment appeal route.

Does this calculator cover a late partnership return?

No. HMRC can charge every partner where a partnership return is late, so partnership penalties should be reviewed separately for the partnership and each affected partner.

What if HMRC gave me a different filing deadline?

Enter the deadline printed on the notice in the optional field. This is useful where a notice to file was issued late or another statutory filing date applies. Check the notice before relying on the result.

Confidential enquiry

Need a late filing penalty checked?

Tell us the tax year, filing deadline, filing date and penalty notices received. Do not include your UTR, National Insurance number, authentication codes or bank details.