Your company's financial year just ended. The clock is ticking on your year-end accounts. You have nine months to file your statutory accounts with Companies House and twelve months to submit your Corporation Tax return to HMRC. Miss either deadline and the penalties start automatically - no warnings, no grace period.
TL;DR: UK limited companies must file annual accounts with Companies House within 9 months of their year end, and a Corporation Tax return with HMRC within 12 months. Late filing penalties start at £150 and rise to £1,500. Companies House issued £34.4 million in late filing fines in 2023-24 alone. This checklist covers what you need to prepare, when each deadline falls, and how to avoid common mistakes.
What Are Year-End Accounts and Who Needs to File Them?
Every UK limited company - active or dormant - must prepare and file annual accounts with Companies House. There are no exceptions. Even if your company had zero revenue, you still need to file. Your statutory accounts typically include a balance sheet, a profit and loss account, notes to the accounts, and a directors' report. Smaller companies can file simplified versions, but the obligation itself remains the same. With over 5.4 million companies on the Companies House register as of December 2025, this is a filing requirement that affects a huge number of business owners across the UK.
When Are the Filing Deadlines?
The two main deadlines run on different clocks, which catches many directors off guard.
Companies House accounts are due 9 months after your accounting reference date (your financial year end). If your year end is 31 March, your accounts are due by 31 December. For your first year of trading, you get 21 months from incorporation or 9 months from your accounting reference date - whichever is longer.
HMRC Corporation Tax has two separate deadlines. You must pay any tax owed 9 months and 1 day after your accounting period ends. The CT600 return itself is due 12 months after your accounting period ends. So for a 31 March year end, your tax payment is due by 1 January and your return by 31 March the following year.
In our experience, the gap between these deadlines is where mistakes happen. Directors pay their tax on time but forget about the CT600, or file accounts with Companies House and assume HMRC is covered too. They are separate filings to separate bodies.
What Happens If You File Late?
Companies House penalties are automatic. There is no appeal process based on "I forgot" or "my accountant was busy." The penalty structure for private limited companies is straightforward:
- Up to 1 month late: £150
- 1 to 3 months late: £375
- 3 to 6 months late: £750
- Over 6 months late: £1,500
File late two years running and those figures double. Companies House issued £34.4 million in late filing penalties in the 2023-24 financial year - more than three times the £10.2 million issued in 2019-20. The number of companies fined for being over six months late rose from 3,418 in 2019-20 to 11,463 in 2023-24, according to Companies House data.
HMRC is increasing its own late filing penalties from April 2026. A late CT600 return now attracts a £200 penalty (up from £100), rising to £400 if the return is still outstanding after three months (GOV.UK, 2026).
What Should Your Year-End Preparation Include?
What we see most often is directors leaving preparation until the last few weeks before the deadline. Starting early makes the whole process faster and less stressful. Here is what to work through:
Reconcile Your Bank Accounts
Match every transaction in your accounting software to your bank statements. Look for unreconciled items, duplicate entries, and missing transactions. If you are using cloud accounting software like Xero or QuickBooks, much of this can be automated - but you still need to review the results. Unreconciled items at year end are a red flag for your accountant and a common source of errors in the final accounts.
Review Outstanding Invoices
Chase any unpaid sales invoices before the year end where possible. For invoices you know will not be collected, write them off as bad debts. On the purchase side, make sure all supplier invoices have been recorded, including any that arrived after the year end but relate to the accounting period.
Check Your Fixed Assets Register
Review your fixed assets list. Remove anything that has been sold or scrapped during the year. Add any new purchases. Make sure depreciation has been calculated correctly. Capital allowances - the tax relief you claim on assets - depend on accurate records here. Getting this wrong means either paying too much tax or facing questions from HMRC later.
Sort Out Director Loans and Dividends
If you have drawn money from the company outside of salary or dividends, this sits as a director's loan. An overdrawn director's loan account at year end triggers a Section 455 tax charge of 33.75% on the outstanding balance. Record all dividend payments with proper minutes and ensure the company had sufficient distributable reserves to pay them.
Gather Your Payroll Records
Confirm all RTI submissions to HMRC are up to date. Check that employer's NIC, PAYE, and any student loan deductions have been paid. If you run payroll for yourself as a director, make sure the annual figures match what has been reported.
How Much Corporation Tax Will You Owe?
The UK Corporation Tax rate for 2025-26 remains at 25% for companies with taxable profits above £250,000. Companies with profits of £50,000 or less pay 19% - the small profits rate. Profits between £50,001 and £250,000 fall into the marginal relief band, where the effective rate scales between 19% and 25% (PWC Tax Summaries, 2026).
If you control more than one company, the £50,000 and £250,000 thresholds are divided equally among all associated companies. Two associated companies means each threshold halves - so the small profits rate applies only up to £25,000 per company.
One question clients always ask is whether they can reduce their Corporation Tax bill before the year end. The answer is usually yes, but only through genuine business expenditure. Pension contributions, R&D expenditure, and capital purchases can all reduce your taxable profit if timed correctly. Our tax planning services can help you identify the right deductions for your situation.
Have Companies House Fees Changed?
Yes. From 1 February 2026, Companies House increased its digital filing fees significantly. The confirmation statement fee rose from £34 to £50 for digital filing and from £34 to £110 for paper filing (Companies House, 2026). The ICAEW described these as "significant hikes" and recommended companies plan ahead for the additional cost.
Your confirmation statement is separate from your annual accounts, but both are required. The confirmation statement is due within 14 days of your review date (the anniversary of incorporation or last filing). Missing it can lead to your company being struck off the register.
Your Year-End Accounts Checklist
Work through this before handing over to your accountant:
- Bank accounts reconciled to the last day of your accounting period
- All sales invoices raised and purchase invoices recorded
- Bad debts identified and written off
- Fixed assets register updated with additions, disposals, and depreciation
- Director's loan account balanced - repay any overdrawn amounts before year end if possible
- Dividend paperwork in order with board minutes
- Payroll year-end submissions complete
- Expense claims processed and receipts filed
- Stock counted and valued (if applicable)
- Contracts and leases reviewed for any year-end accruals or prepayments
Getting these items sorted early means your accountant spends less time on queries and more time on the actual accounts - which usually means a lower fee and a faster turnaround. If you are considering outsourcing your bookkeeping, year end is a good time to make that switch, before the next financial year starts.
Frequently Asked Questions
Can I change my company's financial year end?
Yes. You can shorten your accounting period as many times as you like, but you can only extend it once every five years (unless your company is in administration or Companies House grants permission). The change is made by filing a form with Companies House before your current filing deadline.
Do dormant companies need to file accounts?
Yes. Even if your company has not traded, you must file dormant company accounts with Companies House. These are simplified accounts - usually a balance sheet showing minimal activity - but the filing obligation still applies.
What if my accountant files late - am I still penalised?
Yes. The penalty is issued to the company, not the accountant. Directors are legally responsible for ensuring accounts are filed on time, regardless of who prepares them. If your accountant is causing delays, that may be a sign you need a new one.
Do I need an audit?
Most small companies are exempt from audit. You qualify for the exemption if you meet at least two of three criteria: turnover of £10.2 million or less, balance sheet total of £5.1 million or less, or 50 employees or fewer. If you qualify, you can file unaudited accounts.
What records do I need to keep and for how long?
HMRC requires you to keep accounting records for at least 6 years from the end of the accounting period. This includes invoices, receipts, bank statements, payroll records, and any contracts. Digital records are acceptable - you do not need to keep paper copies if your digital records are complete. Learn more about our team and how we help UK businesses stay on top of their compliance.
Need help preparing your year-end accounts or filing your Corporation Tax return? Get in touch with our team - we work with UK limited companies of all sizes and can handle the full filing process for you. No obligation, no jargon - just a clear plan to get your accounts sorted.