Company accounts and Company Tax Return deadlines, and the penalties for filing late

acrenvo.com/guides/company-accounts-deadlines-and-late-filing-penalties, last reviewed 1 November 2026

Martin is fictional. He runs a small joinery company with one other director, and he files the company’s accounts and its Company Tax Return himself. Last year a busy spring pushed the accounts past their deadline, and a penalty notice from Companies House followed. This year he wants a clear picture before the dates come round: when each filing is due, what each body charges when one is late, and whether an appeal is ever worth making. This guide answers those questions from what Companies House and HMRC have published.

The four deadlines a company works to

A company files with two bodies, and each runs its own clock. Companies House wants the annual accounts, and HMRC wants the Company Tax Return and the Corporation Tax. GOV.UK sets the deadlines out like this.

The two clocks usually start from the same day, which helps when planning the year. Your accounting period for Corporation Tax is the time covered by your Company Tax Return. It’s normally the same 12 months as the company financial year covered by your annual accounts. Even so, the deadlines themselves differ, and the Corporation Tax payment falls due before the return does. Companies House makes the same point in its guidance on filing by software. You may have different deadlines for sending your accounts to Companies House and your Company Tax Return to HMRC.

Some companies can save a step by sending both filings at once, and GOV.UK says when that is possible. You may be able to file them together if you have a private limited company that does not need an auditor. Our company filing hub links to GOV.UK’s two lists of software and to the products we compare.

Late accounts at Companies House

Companies House does not wait to be asked before it charges. GOV.UK says: “You’ll automatically receive a penalty notice if your accounts are filed after the deadline.” The amount grows with how late the accounts are.

These figures are for private limited companies only, and GOV.UK points public companies elsewhere. Penalties for public limited companies are different.

A late Company Tax Return at HMRC

HMRC runs its own penalties, separate from Companies House, so a company that misses both deadlines can be charged by both bodies.

A tax determination does not close the matter, because the return is still owed. GOV.UK says what happens next. You must pay the Corporation Tax due and file your tax return. HMRC will recalculate the interest and penalties you need to pay.

Appealing a late filing penalty

Both bodies accept appeals, but each sets its own conditions, so it helps to read them separately. On the HMRC side, GOV.UK says: “If you have a reasonable excuse, you can appeal against a late filing penalty online.” There is one condition to meet first.

HMRC’s form asks for a few details about the penalty, so it is worth gathering them before starting. You’ll need:

• your company’s Unique Taxpayer Reference (UTR)
• the date on the penalty notice
• the penalty amount
• the end date for the accounting period the penalty is for

You’ll also need to explain why you did not file the return by the deadline.

Companies House also takes appeals, and it asks for evidence that the delay was beyond the company’s control. You can appeal a penalty you get for filing your company accounts late. If you want to appeal a penalty you must:

• give a specific reason for not filing your accounts on time
• include all relevant details, such as dates and times
• prove the circumstances were out of your control, for example a fire destroyed your records a few days before your accounts were due

Wait for Companies House to contact you with their decision. Companies House will not collect the penalty while they consider your appeal.

Companies House also lists reasons that are unlikely to succeed, and it is worth reading them before writing an appeal. GOV.UK says that your appeal may not be successful if:

• these were your first accounts
• your company is dormant
• your company is a charity or a flat management company
• you cannot afford to pay
• another director is responsible for filing the accounts
• it was your accountant’s (or anybody else’s) fault
• you did not know when or how to file your accounts
• your accounts were delayed or lost in the post
• the directors live or were travelling overseas

That list matters for Martin, because leaving the filing to the other director, or to an accountant, is not on its own a reason Companies House is likely to accept. If an appeal is turned down, there is a set route for taking it further. If your appeal is rejected and you have additional information to support your case, you can write to the senior casework manager in the Late Filing Penalties Department at the Companies House office that deals with your account. If your appeal to the senior casework manager is unsuccessful, you can write to the independent adjudicators, and ask them to review your case. If your appeal to the independent adjudicator is unsuccessful, you can submit a final application to the Registrar of Companies at the office that deals with your account. You must follow this process, otherwise the registrar will not review your appeal.

The deadlines after April 2028

The dates in the table stay as they are, but from 1 April 2028 Companies House will take accounts only through software. That matters for a late filer, because the website will no longer be there as a quick fallback.

So a company that plans to file at the last minute needs its software and its presenter details set up well before the deadline. The guide to micro-entity and small company accounts after April 2028 works out when the first filing by software falls for each year end, and our monthly counts of the software used to file company accounts show how many companies still use Companies House’s own service. If something was filed on time but turns out to be wrong, the guide to correcting company accounts and amending a Company Tax Return covers that.

Questions about company filing deadlines and penalties