Accounts filing deadline checker
When are a company's accounts due at Companies House? This checker covers later years, first accounts, public companies and a shortened accounting period. No sign-up, and nothing is stored.
The accounting reference date the accounts are made up to.
How the deadline is worked out
Later years. A private company has nine months after its accounting period ends, and a public company six (Companies Act 2006 s.442(2)). Months are counted under s.443: from the last day of a month, the deadline is the last day of the target month.
First accounts. A company's first accounting period starts on the day it is incorporated and, unless changed, ends on the last day of the month of its first anniversary, so it is almost always longer than 12 months. For a first period longer than 12 months the deadline is nine months (six for a plc) from the first anniversary of incorporation, or three months after the period ends, whichever is later (s.442(3)). In practice that is 21 months after incorporation, which is how GOV.UK describes it. A simple “year end plus nine months” gives the wrong answer here.
Exactly where 12 months ends. Twelve months beginning on 10 March end on 9 March. A first period to 9 March the next year is 12 months, so it takes the normal rule; a period to 10 March or later is longer and takes the first-accounts rule.
A shortened period. When the accounting reference date is moved earlier by a notice under s.392, the deadline is the later of the normal one and three months from the date of the notice (s.442(4)). The checker does not cover a period lengthened by notice or an extension granted by Companies House under s.442(5).
Frequently asked questions
When are a private company's accounts due?
Nine months after the end of the accounting period (Companies Act 2006 s.442(2)). Months are counted to the month end when the period ends on one, so a 30 November year end is due 31 August, not 30 August.
When are first accounts due?
If the first accounting period is longer than 12 months, which it is unless the accounting reference date was changed, the deadline is nine months from the first anniversary of incorporation or three months after the period ends, whichever is later (s.442(3)). GOV.UK puts it as 21 months after the date the company was registered. A first period of 12 months or less takes the normal nine-month rule instead.
What is the first accounting reference date?
Unless it is changed, the last day of the month in which the first anniversary of incorporation falls (s.391(4)). A company incorporated on 10 March 2025 has a first accounting reference date of 31 March 2026. A first period must be more than six months and not more than 18 months long.
Are public companies different?
Yes. A public company has six months after the period ends, and 18 months after incorporation for first accounts longer than 12 months.
What if the accounting period was shortened?
If the change is filed late in the period, s.442(4) gives the later of the normal deadline and three months from the date of the notice. Tick the box in the checker and enter the date the change was filed.
Does the deadline move for a weekend?
The checker shows the date set by the Act and does not move it for a weekend or bank holiday. Plan to file before it.
Related tools
Companies House deadline check looks up live dates for up to 10 company numbers. Companies House penalty estimator shows what late accounts cost. UK statutory deadline calculator adds Corporation Tax and CT600.
Sources: Companies Act 2006 section 442, section 443 and section 391; GOV.UK, Accounts and tax returns for private limited companies, read 3 November 2026. This tool is general guidance, not legal advice. Check the date Companies House shows on the company's page.