How to File Your Limited Company Accounts and Tax Returns in 2025/26
Running a limited company in the UK involves more than generating profit. Each year, directors must comply with multiple statutory filing and payment obligations.
One of the most common causes of penalties is confusion between Companies House requirements and HMRC requirements. They are separate authorities, with separate deadlines, separate enforcement systems, and separate penalties.
In addition, recent updates have tightened compliance expectations. Companies House updated confirmation statement requirements in February 2026 and is phasing in mandatory identity verification from 18 November 2025.
This guide explains:
- What limited companies must file each year
- The exact deadlines in 2025/26
- What happens if you miss them
- How the workflow fits together
- A practical compliance checklist
If you are a director, this is the structure you should be working to every year.
The Three Core Annual Obligations for Every Limited Company
Every UK private limited company must deal with three primary annual requirements:
-
Filing annual accounts with Companies House
-
Paying Corporation Tax to HMRC
-
Filing a Company Tax Return (CT600) with HMRC
These are separate legal obligations.
Paying Corporation Tax does not mean you have filed your accounts. Filing accounts does not mean you have submitted your Company Tax Return. Each step must be completed independently.
Step 1: Filing Annual Accounts with Companies House
When Are Annual Accounts Due?
For most private limited companies, annual accounts must be filed:
Nine months after the end of your financial year.
For example:
- Financial year-end: 31 March 2026
- Accounts filing deadline: 31 December 2026
This deadline applies regardless of profit or loss.
Newly incorporated companies may have slightly different deadlines for their first accounts, but thereafter the nine-month rule applies consistently.
What Must Be Filed?
Depending on company size, you may file:
- Full statutory accounts
- Abbreviated accounts (for small companies)
- Micro-entity accounts
Even small or dormant companies must file accounts.
The documents typically include:
- Balance sheet
- Profit and loss account (if required)
- Notes to the accounts
- Directors’ approval statement
Accounts must be approved by the board and signed by a director before filing.
What Happens If You Miss the Accounts Deadline?
Companies House applies automatic late filing penalties.
The penalty increases depending on how late the accounts are filed:
- Up to 1 month late
- 1 to 3 months late
- 3 to 6 months late
- More than 6 months late
If accounts are filed late two years in a row, penalties are doubled.
Importantly:
Penalties are issued automatically, even if your accountant was responsible for the delay. Directors remain legally responsible.
Continued failure to file can lead to:
- Prosecution of directors
- Company strike-off proceedings
- Damage to credit rating
- Banking complications
Step 2: Paying Corporation Tax to HMRC
Corporation Tax payment is separate from filing accounts.
When Is Corporation Tax Due?
Corporation Tax must be paid:
Nine months and one day after the end of the accounting period.
Using the earlier example:
- Year-end: 31 March 2026
- Corporation Tax payment deadline: 1 January 2027
This deadline usually falls before the Company Tax Return deadline.
You must calculate and pay the tax before filing the formal return.
What Happens If You Pay Late?
If Corporation Tax is paid late:
- HMRC charges interest from the due date
- Persistent late payment can lead to penalties
- Debt collection action may begin
HMRC enforcement is separate from Companies House. Even if your accounts are filed on time, HMRC may still pursue unpaid tax.
For most small and medium-sized companies, Corporation Tax is paid annually. Large companies may fall under quarterly instalment payment rules.
Step 3: Filing the Company Tax Return (CT600)
The Company Tax Return is filed with HMRC, not Companies House.
When Is the CT600 Due?
The deadline for filing the Company Tax Return is:
Twelve months after the end of the accounting period.
Example:
- Year-end: 31 March 2026
- CT600 filing deadline: 31 March 2027
This is three months after the Corporation Tax payment deadline.
You must pay the tax before filing the return.
What Happens If You File the CT600 Late?
HMRC applies automatic penalties:
- £100 immediately after missing the deadline
- Additional £100 if more than 3 months late
- Further penalties at 6 months
- Tax-geared penalties at 12 months
Repeated late filing increases penalties significantly.
Unlike Companies House penalties, HMRC penalties escalate based on behaviour and persistence.
Confirmation Statement: A Separate Annual Requirement
In addition to accounts and tax filings, every company must submit a Confirmation Statement to Companies House.
This confirms that the company’s statutory information is accurate, including:
- Registered office address
- Directors
- Shareholders
- Persons with Significant Control (PSCs)
- Share capital structure
It must be filed at least once every 12 months.
As of February 2026, Companies House tightened confirmation statement requirements and increased scrutiny around shareholder and PSC disclosures.
Failure to file is a criminal offence and can result in strike-off action.
Identity Verification from 18 November 2025
Companies House is implementing identity verification requirements as part of wider corporate transparency reforms.
From 18 November 2025, identity verification will begin to apply in phases.
Directors and Persons with Significant Control will need to verify their identity before certain filings can be made.
This reform is intended to reduce fraud and improve transparency but will add an additional compliance layer for companies.
Companies should ensure:
- Director records are up to date
- PSC registers are accurate
- Identification documents are ready
Failure to comply with identity verification requirements may prevent filings from being accepted.
Full Filing Timeline Example
Assume a company with a 31 March 2026 year-end.
| Obligation | Authority | Deadline |
|---|---|---|
| Annual Accounts | Companies House | 31 December 2026 |
| Corporation Tax Payment | HMRC | 1 January 2027 |
| Company Tax Return (CT600) | HMRC | 31 March 2027 |
| Confirmation Statement | Companies House | 12 months from last filing |
These deadlines operate independently.
What Happens If Multiple Deadlines Are Missed?
If a company fails to:
- File accounts
- Pay Corporation Tax
- File its CT600
- File its confirmation statement
Multiple enforcement actions may occur simultaneously.
Companies House may:
- Issue late filing penalties
- Publish strike-off notices in the Gazette
HMRC may:
- Charge interest
- Issue penalties
- Begin debt recovery action
Banks may:
- Freeze accounts during strike-off proceedings
The situation can escalate quickly if ignored.
Annual Limited Company Compliance Checklist
Directors should operate a structured annual workflow.
After Year-End:
- Finalise bookkeeping
- Review director’s loan account
- Confirm dividend legality
- Prepare draft accounts
- Estimate Corporation Tax liability
Before 9 Months After Year-End:
- Approve and sign accounts
- File accounts with Companies House
Before 9 Months and 1 Day:
- Pay Corporation Tax
Before 12 Months After Year-End:
- File CT600 with HMRC
Annually:
- File confirmation statement
From 18 November 2025 onwards:
- Ensure identity verification compliance
Maintaining a compliance calendar significantly reduces risk.
Why Businesses Miss Deadlines
Common causes include:
- Confusing Companies House with HMRC
- Assuming the accountant handles everything automatically
- Poor bookkeeping
- Cash flow constraints delaying tax payments
- Not understanding rolling confirmation statement dates
In most cases, penalties arise from process gaps rather than deliberate non-compliance.
Final Summary: What Every Director Must Know in 2025/26
Every limited company must manage:
- Annual accounts (Companies House)
- Corporation Tax payment (HMRC)
- Company Tax Return filing (HMRC)
- Confirmation Statement (Companies House)
- Identity verification requirements (from 18 November 2025)
Each has its own deadline and penalty regime.
Missing one does not excuse the others.
The most effective way to avoid penalties is a structured, proactive compliance workflow that tracks each deadline separately.
If you are unsure about your company’s filing position, a compliance review should be carried out before deadlines approach.
Individual circumstances vary, and professional advice should be taken where uncertainty exists.
