TITLE: How to File Your Limited Company Accounts and Company Tax Return in 2026
Your UK limited company has two core year-end filing responsibilities: statutory accounts for Companies House and a Company Tax Return for HMRC. They are connected, but they are not the same submission.
This guide explains the practical filing process for small UK limited companies as of September 2026, including the closure of the joint filing service, current deadlines and what the paused Companies House reforms mean for you.
Understand the two filings before you start
Your annual compliance process normally includes:
- Statutory accounts: filed with Companies House.
- Company Tax Return, known as a CT600: filed with HMRC.
- Corporation Tax payment: paid separately to HMRC, normally before the CT600 filing deadline.
- Supporting records: bookkeeping, bank reconciliations, VAT records, payroll information, stock records and tax adjustments.
The former HMRC and Companies House joint online filing service, known as CATO, closed on 31 March 2026. You can no longer rely on one combined submission to complete both obligations.
You should now plan for two separate filings:
- Prepare and file the accounts with Companies House using the appropriate commercial software or approved filing route.
- Prepare and file the CT600 and tax computations with HMRC using commercial Corporation Tax software.
The official GOV.UK guidance on filing accounts and Company Tax Returns confirms that the two authorities receive separate information. This separation makes a controlled year-end process more important.
Know the deadlines that protect your company
For a typical private limited company, the main deadlines are:
| Obligation | Normal deadline |
|---|---|
| Companies House statutory accounts | 9 months after the accounting reference date |
| Corporation Tax payment | Normally 9 months and 1 day after the Corporation Tax accounting period ends |
| CT600 Company Tax Return | 12 months after the Corporation Tax accounting period ends |
A crucial point is often misunderstood: Companies House accounts are normally due nine months after the year-end, not nine months and one day. The extra day normally applies to the Corporation Tax payment deadline.
For example, if your accounting period ends on 31 December 2026:
- Accounts must normally reach Companies House by 30 September 2027.
- Corporation Tax payment is normally due by 1 October 2027.
- The CT600 is normally due by 31 December 2027.
The date that matters for Companies House is the date the accounts are delivered and accepted. Filing close to the deadline leaves less time to correct rejected accounts, so submitting early gives you valuable protection.
Your first accounts may follow a different timetable. Check the company’s incorporation date and accounting reference date before setting the deadline.
Prepare your bookkeeping before preparing accounts
Accurate statutory accounts begin with clean monthly bookkeeping. Do not wait until the deadline month to investigate missing transactions.
Complete these checks first:
Reconcile every bank account
Match the accounting records to each business bank account. Include payment processors and online wallets where relevant.
For an ecommerce or digital company, this may include:
- Shopify Payments
- Stripe
- PayPal
- Amazon or other marketplace settlements
- Foreign currency accounts
- Business credit cards
Reconciliation identifies missing income, duplicated expenses and unexplained balances. It also gives you confidence that the profit figure is based on complete data.
Check VAT and payroll records
Agree the bookkeeping to submitted VAT returns and payroll reports. Investigate differences before year-end accounts are finalised.
This step matters because VAT control account errors can distort both the balance sheet and Corporation Tax computation. Payroll liabilities, PAYE, National Insurance and pension amounts should also be correctly recorded at the year-end.
Record stock, accruals and prepayments
A Shopify brand may need a year-end stock valuation. A digital agency may need to account for work completed but not yet invoiced.
Also review:
- Insurance and software subscriptions paid in advance
- Supplier invoices received after year-end
- Services received but not yet invoiced
- Customer deposits and deferred income
- Bad debts
- Fixed assets and depreciation
These adjustments help ensure that income and costs are recorded in the correct accounting period.
Review director and shareholder balances
Check director loan accounts and payments made personally on behalf of the company. Misclassified withdrawals can create tax and reporting problems.
Keep supporting documentation for dividends, expenses, loans and reimbursements. This reduces questions during accounts preparation and makes the approval process faster.
Choose the correct accounts format
Your company’s size and circumstances determine the accounts framework available to you. Small and micro-entity companies may have reduced reporting options, but the directors remain responsible for ensuring that the accounts are properly prepared and approved.
Under the current position, eligible small companies can generally continue to file abridged or filleted accounts. A filleted set may leave information such as the profit and loss account off the public Companies House record, where permitted.
The filing format does not remove the need to prepare complete internal accounting records. Your CT600 still requires a reliable profit calculation, even if some information is not displayed publicly.
Check the latest Companies House accounts guidance before filing because eligibility and filing options depend on the company’s circumstances.
Understand what the paused reforms mean
The proposed Companies House accounts reforms have created understandable uncertainty for small companies.
The original timetable for wider changes was paused and reset. The government is also consulting on modernising the UK corporate reporting framework until 11:59pm on 30 November 2026. You can read the Modernising Corporate Reporting consultation on GOV.UK.
The practical position for your business is:
- Continue using the current accounts filing rules unless new legislation changes them.
- Eligible small companies can still use current abridged or filleted filing options.
- Do not file a profit and loss account publicly simply because you have seen reports about planned reforms.
- Monitor official Companies House announcements rather than relying on old software messages or social media posts.
- Government has committed to giving companies at least 21 months’ notice before any new implementation date.
The direction of travel is clearly more digital reporting and improved data quality.
