Guide
Limited company deadlines and what happens if you miss one
A limited company answers to two bodies: Companies House and HMRC. Each has its own deadlines and its own penalties, and filing with one does not satisfy the other.
In short
A private limited company must file accounts at Companies House nine months after its year end, pay corporation tax nine months and one day after it, and file its CT600 return twelve months after it. A confirmation statement is due at least once a year, within 14 days of the review date.
The core deadlines
| Obligation | Filed with | Deadline |
|---|---|---|
| Annual accounts | Companies House | 9 months after the accounting reference date |
| First accounts | Companies House | 21 months after incorporation |
| Corporation tax payment | HMRC | 9 months and 1 day after the end of the accounting period |
| Corporation tax return (CT600) | HMRC | 12 months after the end of the accounting period |
| Confirmation statement | Companies House | Within 14 days after the review date |
| Director, PSC and share changes | Companies House | Within 14 days of the change |
| Register for corporation tax | HMRC | Within 3 months of starting to trade |
Example: a company with a 31 March 2026 year end must file accounts by 31 December 2026, pay its corporation tax by 1 January 2027 and file its CT600 by 31 March 2027.
Companies House late filing penalties
| Accounts filed late by | Penalty (private company) |
|---|---|
| Up to 1 month | £150 |
| 1 to 3 months | £375 |
| 3 to 6 months | £750 |
| More than 6 months | £1,500 |
The penalty is doubled if accounts are filed late in two consecutive years. It is automatic and charged to the company, and appeals succeed only in genuinely exceptional circumstances. Persistent non-filing can lead to prosecution of directors, disqualification and the company being struck off.
The confirmation statement
The confirmation statement confirms that the company's details on the public register are correct. From 1 February 2026 the online filing fee is £50. There is no automatic penalty for filing late, but failing to file is an offence and can lead to the company being struck off. Since November 2025 it is also how existing directors supply their identity verification code. See our identity verification guide.
HMRC penalties
HMRC charges its own fixed penalties for a late CT600, rising the longer it is outstanding, plus tax-geared penalties if a return is very late. Interest runs on corporation tax paid late. These are separate from, and in addition to, any Companies House penalty.
How to never miss one
- Know your accounting reference date and review date; both are on the public register.
- Put every deadline in one calendar, including VAT and payroll.
- Aim to finish accounts within four to six months of the year end, not nine.
- Verify every director's identity well before the next confirmation statement.
Our 2026/27 tax deadline calendar lists every date in one place.
Common questions
Questions we are often asked
Nine months after the company's year end for a private limited company. First accounts are due 21 months after incorporation.
For a private company, £150 if up to a month late, £375 up to three months, £750 up to six months and £1,500 after that. The penalty doubles if accounts are late two years in a row.
Payment is due nine months and one day after the end of the accounting period, and the CT600 return twelve months after it. Companies with profits over £1.5 million pay in quarterly instalments.
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