Late filing penalty calculator
Behind on a Self Assessment return or Companies House accounts? See what the delay has cost so far, and what filing today saves.
Your penalty so far
Change the details, the results update instantly.
Self Assessment penalties can also include interest on unpaid tax, not shown here. Always take advice before acting.
How it works
Self Assessment charges a fixed £100 penalty as soon as a return is late, then daily penalties of £10 a day after three months, up to a 90-day cap, then a further 5% of the tax due (minimum £300) at six and twelve months. Companies House accounts penalties for a private limited company step up through fixed bands the longer accounts are outstanding: higher for each additional month, and double if you're late two years running, tick the box above if that applies to you. If you're already behind, our late accounts rescue service is built to get you back on track quickly.
Frequently asked questions
Do these penalties apply on top of any tax I owe?
Yes, filing penalties are separate from the tax itself. If tax is unpaid, HMRC also charges interest on the amount owed, which isn't included in this filing penalty figure.
Can penalties be appealed?
Yes, if you have a reasonable excuse, HMRC and Companies House will consider an appeal. Book a call if you think your circumstances qualify, or see our self-assessment service if you'd rather hand the whole filing over.
Do the daily £10 penalties really add up to £900?
Yes, £10 a day for up to 90 days after the three-month point is a maximum of £900, on top of the initial £100, which is why acting early matters.
Are Companies House penalties different for late accounts filed twice in a row?
Yes, the penalty doubles if your accounts are late for two financial years running. Tick the box that appears when you select Companies House accounts above, and this calculator applies the doubling for you.
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These results are a simplified illustration based on 2026/27 rates, not advice. Your real position depends on your full circumstances. For a personalised answer, book a free consultation.
Numbers looking complicated?
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