Last updated: 5 October 2026 · Written by Axel
A Companies House late filing penalty for a private limited company starts at £150 and climbs to £1,500, and it is completely separate from HMRC. Miss your year end paperwork and you can be fined twice for the same year: once by Companies House for late accounts, and again by HMRC for a late Company Tax Return (CT600), which now starts at £200. Both are automatic, both apply even if you owe no tax, and both get worse the longer you leave them. Here is how each one works, what a real missed year costs, and how to stop the meter running.
Two regulators, two deadlines, two sets of fines
Most small company directors think of "filing" as one job. It is two, sent to two different bodies that do not talk to each other about penalties:
- Companies House wants your annual accounts. For a private company the deadline is 9 months after the end of your accounting period. Your first accounts are due within 21 months of incorporation, or 3 months from the accounting reference date if that is later.
- HMRC wants your Company Tax Return (CT600, with your accounts and computations attached). The deadline is 12 months after the end of the accounting period it covers.
- HMRC also wants the tax itself, usually 9 months and 1 day after the end of the accounting period. That is earlier than the return.
So the money is due before the return, and the accounts are due before both. If you only remember one date, remember the 9 month one.
The Companies House late filing penalty
Companies House does not care whether you made a profit. The penalty is a flat amount based purely on how late the accounts arrive, measured from the day they were due. These are the current late filing penalties from Companies House for a private company:
| How late the accounts are | Penalty |
|---|---|
| Up to 1 month | £150 |
| More than 1 month, up to 3 months | £375 |
| More than 3 months, up to 6 months | £750 |
| More than 6 months | £1,500 |
Two things make this nastier than it looks:
- It doubles if you are late two years running. File late in two successive financial years and the second penalty is twice the table above. A second year more than 6 months late is £3,000.
- Not filing is also a criminal offence. The penalty is the civil part. Directors can be personally fined in the criminal courts for not filing accounts or confirmation statements.
HMRC late CT600 penalties
HMRC's penalties went up for returns with a filing date on or after 1 April 2026. Per HMRC's Corporation Tax penalty notes (CT211) and the Company Tax Return penalties page:
- 1 day late: £200
- 3 months late: another £200 (£400 in total)
- Late 3 times in a row: if the returns for the previous two periods were also late and already drew penalties, the £200 penalties become £1,000 each
- 6 months late: HMRC estimates your Corporation Tax bill (a "tax determination") and you have to pay it. You cannot appeal a determination; the way to replace it is to file the real return.
- 18 months after the end of the accounting period: a tax-geared penalty of 10% of the unpaid tax, rising to 20% if the return is still not in 2 years after the period ended.
Interest also runs on any Corporation Tax paid after the payment deadline. That is separate from the filing penalties above.
Companies House vs HMRC side by side
| Companies House | HMRC | |
|---|---|---|
| What it wants | Annual accounts | CT600 plus the tax |
| Deadline | 9 months after year end | Return: 12 months. Tax: 9 months and 1 day |
| First penalty | £150 | £200 |
| Maximum flat penalty | £1,500 (£3,000 if late two years running) | £400, or £2,000 for a third late return in a row |
| Tax-geared penalty | None | 10%, then 20% of unpaid tax |
| Applies if no tax owed? | Yes | Yes, the flat penalties do |
| Appeal route | Companies House online appeal | HMRC appeal, within 30 days of the notice |
| What wins an appeal | Exceptional, unforeseen events near the deadline | A reasonable excuse, then filing as soon as you can |
A worked example: one director, one missed year
Take a one-director electrical company with a year end of 30 June 2025. Life got busy and nothing was filed. The dates were:
- Accounts to Companies House: due 31 March 2026
- Corporation Tax payment: due 1 April 2026
- CT600 to HMRC: due 30 June 2026
The director finally files both in the second week of October 2026:
- Companies House: the accounts are more than 6 months late, so the penalty is £1,500. If last year's accounts were also late, it is £3,000.
- HMRC: the CT600 is more than 3 months late, so £200 + £200 = £400. The filing date is after 1 April 2026, so the new amounts apply.
- Interest on whatever Corporation Tax was owed, running from 1 April 2026.
That is £1,900 in flat penalties for one year of paperwork that, for a simple company, is a few hours' work. If the CT600 were still missing on 31 December 2026, 18 months after the year end, HMRC would add 10% of any unpaid tax on top.
The lesson: the Companies House penalty is the big one for small companies, and it is the one that arrives first.
Dormant companies get fined too
A dormant company still has to file accounts, and Companies House lists "your company is dormant" as a reason an appeal is unlikely to succeed on its own. If HMRC has sent you a notice to deliver a Company Tax Return, you must file one even if there is no Corporation Tax to pay. Dormant accounts are short, so there is no excuse to let them slip. Our guide on what a dormant company has to file covers exactly what is needed.
How to appeal a late filing penalty
Be realistic before you start. Both regulators set the bar high, and Companies House in particular has very limited discretion.
Appealing to Companies House
Use the Companies House appeal a late filing penalty service. You need the company number, the penalty reference, your reason and any supporting documents. You can only submit one appeal per penalty notice, so make it count.
What tends to work: unexpected events close to the deadline, such as serious illness or a death, or a mistake by Companies House. What Companies House says will not work on its own:
- the company is dormant
- you cannot afford to pay
- you relied on your accountant
- these were your first accounts
Honest view: if your reason is on the list above, pay the penalty and put your energy into not being late next year.
Appealing to HMRC
HMRC accepts a "reasonable excuse": a close relative dying shortly before the deadline, an unexpected hospital stay, a computer or software failure while you were preparing the return, or a fire, flood or theft. Not getting a reminder, or finding the online system too hard, does not count. You must file the CT600 before you appeal, and appeal within 30 days of the penalty notice. Once the excuse ends, file as soon as you are able.
If your situation is messy (several years unfiled, a determination you think is wildly wrong, or a strike-off letter), that is the point to talk to your own accountant. This is genuinely worth paying for.
A short deadline checklist
- Write down your year end and the three dates that follow: +9 months (accounts and tax), +12 months (CT600).
- Check them on the Companies House register and against our Corporation Tax filing deadlines page.
- Aim to file the accounts and CT600 together, as soon as the year closes. Doing them at once means the figures match and the 9 month deadline never sneaks up on you.
- If you file micro-entity accounts, decide whether you want filleted accounts on the public register.
- Make sure the company has its Corporation Tax UTR and you can log in to your Government Gateway before deadline week. If you are also missing a personal UTR for Self Assessment, see how to register for a UTR.
- Already late? File now. Every penalty band above is about time, so a day sooner can be a band cheaper.
Quick answers
Frequently Asked Questions
01Does Companies House charge a late filing penalty if my company made no money?
Yes. The penalty depends only on how late the accounts are, not on profit or tax. Dormant companies are penalised in exactly the same way.
02Can I be fined by both Companies House and HMRC for the same year?
Yes. They are separate regulators with separate deadlines and separate penalties. A year with late accounts and a late CT600 gets two sets of fines.
03How much is the HMRC penalty for a late CT600?
For returns with a filing date on or after 1 April 2026 it is £200 at 1 day late and another £200 at 3 months. After 18 months a tax-geared penalty of 10% of unpaid tax is added, rising to 20% after 2 years.
04Does the penalty stop if I file the next day?
The flat penalty for the band you are in is already charged, but filing stops you sliding into the next band. With HMRC it also replaces any estimated tax determination with your real figures.
05Is relying on my accountant a valid excuse?
Not for Companies House, which lists it as a reason that will not succeed. The directors are responsible for filing, whoever prepares the accounts.
File both before the clock runs
If your company is a simple micro-entity, you can do this yourself. A.X.E.L Filing prepares your micro-entity accounts and CT600 and files them to Companies House and HMRC with your own Government Gateway login: £49 for both together (£20 for a dormant company, £29 for an amendment), no subscription. It will not make an existing penalty go away, but it helps you file on time next year.
A.X.E.L Filing
Accounts and CT600, filed in one sitting.
Prepare your micro-entity accounts and Corporation Tax return together, then file them to Companies House and HMRC yourself. No accountant fees, no subscription.
£20 for a dormant company
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