When are my first company accounts due?

Last reviewed: 29 September 2026 · Reviewed by IFM's qualified accountant

The first year feels confusing because Companies House accounts and HMRC Corporation Tax do not use one identical timetable. One set of statutory accounts can cover more than 12 months, but a Corporation Tax accounting period cannot. That can mean one Companies House filing and two Company Tax Returns.

Where should you check the first accounts deadline?

When a company is incorporated, Companies House sets an accounting reference date. The first statutory accounts normally run from the incorporation date to that date. The company’s public record shows both the period covered by the next accounts and the filing deadline.

Use that public record as the starting point rather than calculating the date from memory. The normal 21-month headline is useful, but changes to the accounting reference date, an unusual first period or a filing extension can alter what the company must do.

For later years, a private company normally files within nine months of the end of its financial year. The first-year allowance is therefore a one-off rule, not an ongoing 21-month cycle.

Why can first accounts cover more than 12 months?

The first financial year often runs for slightly more than a year because the accounting reference date is set by reference to the incorporation month. That is permitted for Companies House accounts, subject to the rules on financial years.

Corporation Tax works differently. An accounting period for Corporation Tax cannot exceed 12 months. If the statutory accounts cover, for example, 12 months and several extra days or weeks, HMRC may require two Company Tax Returns: one for the first 12 months and one for the remaining period.

This does not mean two sets of published accounts. It means the figures from one set of accounts are divided between the relevant Corporation Tax returns. The tax payment and return dates attach to the accounting period each return covers.

How do accounts differ from the Company Tax Return?

The Companies House accounts deadline and HMRC return deadline should be recorded separately:

first statutory accounts: generally 21 months after incorporation;
Corporation Tax payment: normally nine months and one day after the end of each relevant accounting period for a company below the instalment-payment threshold; and
Company Tax Return: normally 12 months after the end of the accounting period it covers.

Because payment comes before the return filing deadline, the company needs reliable accounts and tax calculations early enough to pay. Waiting until the last permissible date for the Company Tax Return is not a plan for paying on time.

Companies with taxable profits above £1.5 million may fall within Corporation Tax instalment rules. The threshold can be reduced where there are associated companies, so a growing or group company should not assume the standard nine-month-and-one-day payment date applies.

What happens if the company did not trade immediately?

A new company can be dormant for Corporation Tax between incorporation and the date it starts trading. HMRC asks for the trading start date when Corporation Tax services are added to the business tax account.

What happens next depends on the dates and on any notice HMRC has issued. GOV.UK explains that a company may have one return for the trading period or may need separate returns for dormant and trading periods. A notice to deliver a Company Tax Return must not be ignored: if HMRC has issued one, the return normally still needs to be filed for the period stated unless HMRC changes the requirement.

Dormancy for HMRC does not remove the Companies House accounts obligation. A company that has had no significant accounting transactions may be able to file simpler dormant accounts, but it still files annual accounts and a confirmation statement.

Can you change the first company year end?

A company can change its accounting reference date for the current financial year or the immediately previous one, subject to the rules. It may shorten a financial year more than once. It can normally lengthen a financial year to a maximum of 18 months and generally only once in five years, unless an exception applies.

Changing the year end changes the accounts deadline, except when lengthening the first financial year under the stated exception. A change can produce an earlier deadline, and Companies House warns that a late filing penalty can arise if the new deadline has already passed. An overdue company cannot change its year end.

If the financial year is lengthened beyond 12 months, the Corporation Tax position also needs attention because HMRC still limits an accounting period to 12 months. GOV.UK says the company must update its accounting-period dates with HMRC when a year end is lengthened.

Do not change a year end simply to gain time without checking all the consequences. It can affect comparability, tax periods, internal reporting and the preparation timetable.

What happens when first accounts are late?

Late accounts receive an automatic Companies House penalty. For a private company, the current scale is:

How late the accounts are	Penalty
Up to one month	£150
More than one month and up to three months	£375
More than three months and up to six months	£750
More than six months	£1,500

The penalty is doubled if accounts are late in two successive financial years. “These are our first accounts” is not normally a successful reason for appeal. Directors remain responsible for delivery even where an accountant prepares the accounts.

If an unforeseen event outside the company’s control will prevent filing, it can apply for more time before the normal filing deadline. Companies House gives unexpected illness or a fire destroying records shortly before the deadline as examples. An extension is not automatic, and the safest course is still to file by the original date if possible while awaiting a decision.

What timetable should a new company follow?

As soon as the company is formed, record the first accounts due date and the confirmation-statement review date. When trading starts, make sure HMRC has the correct date and that the Corporation Tax accounting periods in the business tax account match reality.

Several months before the accounts deadline, reconcile the bank, sales, costs, payroll, director transactions, loans, assets and taxes. Resolve unclear items while records and memories are still fresh. Agree who approves the accounts and how the director’s signature will be obtained.

Keep the incorporation documents, share issue records, business bank statements and evidence of the first trading activity together. The first accounts often contain setup costs, money introduced by a director and transactions paid personally before the bank account was ready. Recording these properly at the time is much easier than reconstructing them near the deadline. If the company has not traded, preserve the evidence supporting dormancy and avoid casual bank movements that may need to be treated as significant transactions.

Ask for a draft timetable that includes the tax calculation, not only the Companies House submission. That gives the director time to understand the result, arrange the Corporation Tax payment and correct the records before the formal filing dates arrive.

Use the Deadline Finder for standard first accounts, first confirmation statement and Corporation Tax dates. For VAT, payroll, personal tax and other obligations, check the tax deadlines calendar and your official records.

What should you read next?

What do people also ask about this topic?

Why are first company accounts due after 21 months?

The first filing allowance gives a private company 21 months from incorporation in the usual case. Its first financial year often covers slightly more than 12 months because Companies House sets the accounting reference date at the end of the incorporation anniversary month.

Do first company accounts cover more than one year?

Often, yes. They begin on incorporation and normally end on the accounting reference date in the following year, so the period can exceed 12 months. Corporation Tax periods cannot exceed 12 months, which can produce two tax returns for one set of accounts.

Can I extend the deadline for first company accounts?

A company may change its accounting reference date within the rules or apply for more time before the deadline when an exceptional event prevents filing. Neither route should be assumed to apply. Check the live register and Companies House guidance before acting.

Do dormant companies still file first accounts?

Yes. A company with no significant accounting transactions may qualify to file dormant accounts, but it still has annual accounts and confirmation statement obligations. HMRC dormancy and Companies House dormancy are related concepts but must be handled with the correct body.

Which official sources support this guide?

General guidance, not advice for your situation.