How to file your company accounts at Companies House

Understand your deadline

Every UK limited company must file annual accounts at Companies House after each financial year end. The deadline for a private limited company is nine months after your accounting reference date (ARD). Your ARD defaults to the last day of the month in which your company was incorporated, but you can change it via a form AA01 — something worth considering if your trading cycle makes a different year-end more logical.

Your first accounts are treated differently. They cover the period from incorporation to your first ARD, and the filing deadline is 21 months from the date of incorporation. After that, the nine-month rule applies consistently. Diary the deadline the moment your year-end passes. Late filing penalties begin automatically and escalate the longer you leave it — from £150 for a month late to £1,500 for more than six months. Repeat lateness doubles the penalty. There is no grace period and HMRC's obligation to pay the fine does not disappear even if you file shortly after the deadline.

Choose the right accounts format

The format and content of your accounts depends on the size of your company. HMRC and Companies House use the same size thresholds (confirm current limits with your accountant, as they can change):

• Micro-entities — the smallest companies can file abridged accounts with minimal disclosure, though these provide little information for lenders or credit agencies assessing you.
• Small companies — can file abbreviated accounts at Companies House (less detail than is filed with HMRC), but from April 2027 new rules require fuller disclosure. Take current advice.
• Medium and large companies — must file full accounts including a directors' report, strategic report (large only), and audited financials.

Filing the minimum legally required is always an option, but consider how it affects your company's credit profile. Agencies like Experian and Creditsafe score companies partly on the quality and completeness of their public filings. A micro-entity filing that hides turnover and profit can cost you credit availability. Discuss the trade-off with your accountant.

Prepare the accounts: step by step

In practice, most directors work with an accountant to prepare the statutory accounts. Your job is to make that process smooth:

1. Close your bookkeeping for the year — all transactions entered, bank reconciled to the year-end date, expenses claimed, accruals and prepayments processed.
2. Provide your accountant with access to your accounting software or export a final trial balance for the year.
3. Review a draft of the accounts before they are filed. Check the key figures — turnover, profit, net assets, director's loan balance — against your own understanding. Errors are far cheaper to correct in draft than after filing.
4. Approve and sign the accounts as a director. The balance sheet must be signed by a director before filing.
5. File with Companies House — online via the WebFiling service or HMRC's joint filing service, or by post.

At the same time, your accountant will prepare and file a Company Tax Return (CT600) and associated accounts with HMRC. This has a separate deadline — 12 months after your accounting period ends — but is usually handled simultaneously. Keep both on your calendar.

File using Companies House WebFiling

The quickest route for most companies is WebFiling at find-and-update.company-information.service.gov.uk, where you can file accounts and your confirmation statement in one place. You'll need your Companies House authentication code, issued when the company was formed or available by request.

For small companies filing micro-entity or abridged accounts, the portal guides you through a short online form. For fuller accounts, most accountants use software that files directly to Companies House via iXBRL (a structured data format). If your accountant files on your behalf, you'll typically sign the accounts digitally or provide written approval before submission. Either way, check that the filing confirmation arrives and that the accounts show as accepted on the company's public register. Errors that slip through at this stage are visible to anyone who looks.

What to do if you've missed the deadline

File immediately. The penalty is automatic and cannot be waived simply because you didn't know the deadline — the only ground for appeal is a genuine, exceptional reason entirely outside your control. Late is better than later.

If you cannot file because the accounts aren't ready, engage your accountant urgently. Companies House does not grant extensions to private companies except in genuinely exceptional circumstances (such as a natural disaster or serious illness). Voluntary strike-off is not a way to avoid a penalty for accounts that are already overdue — penalties may still be pursued. Where accounts are very late, Companies House can also begin compulsory strike-off proceedings, which creates far larger problems. If you've received a penalty notice, pay it while getting the accounts filed, and then take steps to make sure the same thing cannot happen next year.