Business Woman
Business Woman
CT600

Submit your
Corporation Tax

File your company tax return directly to HMRC online

Late filing results in an automatic £100 penalty that increases over time. We ensure it is accurate and submitted on time.

WHAT is the CT600?

Understanding your CT600 corporation tax obligations

The CT600 is the Corporation Tax return your UK limited company must file with HM Revenue & Customs after the end of its accounting period. It reports your company’s profit, tax liability and required adjustments so HMRC can calculate your Corporation Tax.
Since paper filing is no longer available, digital submission via approved software like ours is mandatory for all UK companies.

Steps

File your CT600 with Easy Digital Filing

1

Find a company to file for

Log in to our cloud software (no installation required) and follow these quick actions:

  • Use Quick Start to find your company by name or number.
  • Choose your filing type (CT600 and/or iXBRL) and your entity size (micro or small).
2

Enter turnover and expenses

Use our templates to enter your financial data, our software calculates your tax liability in real time.

  • Follow our step by step process; enter income, turnover, capital allowances, R&D credits, losses, and loans to participants.
  • View your live, automated corporation tax calculation instantly on-screen.
  • Follow the integrated templates to seamlessly format your accounts for HMRC.

3

Complete iXBRL accounts template

Our built-in validator checks your data as you type, making sure everything complies with HMRC rules

  • Click an error to view the related issue for review.
  • See our knowledge base for guides, or contact us through live chat for additional support.

4

Review CT600 computations and iXBRL accounts

  • Click "Ready to File" to turn your figures into iXBRL format right away.
  • Open the iXBRL viewer to check which fields the software tagged for HMRC.
  • Review your CT600 form and tagged computations on screen to verify your data.
5

Submit CT600 to HMRC

Your CT600 return, tax computations, and iXBRL accounts are now ready to submit to HMRC.

  • Drag and drop any supporting documentation.
  • Click submit to send your filings directly to HMRC.

6

Corporation Tax submission done!

Once you have successfully submitted your return, download your CT600, tax calculation computations and accounts for your records.
Your submission is complete!

Start your CT600
Video

A Smarter Way to File All in One Place:

We understand the importance of simplicity and support for small businesses. That’s why, unlike other providers, our service lets you file your CT600, iXBRL accounts to HMRC and Companies House all at once—no switching platforms, no extra steps

What's included

Complete Digital Filing, From Preparation to Submission

  • CT600 corporation tax return
  • Corporation tax liability calculation
  • iXBRL tagging of accounts (if uploaded)
  • QuickStart guided workflow
  • Direct submission to HMRC
  • Digital confirmation receipt

Does your company need to submit a CT600?

You must file a CT600 for your company if it is registered as a UK limited company and has:

  • Trading income
  • Investment income
  • Dormant status (yes, even dormant companies still usually need a return)
  • Any taxable activities during the accounting period
Important update

HMRC’s free online filing service for CT600 returns is closing on 31 March 2026. After this date, you must file using approved software like Easy Digital Filing — or through an accountant.

Trusted & Recognised

HMRC recognised
software provider

Registered HMRC Agent

We’re a registered HMRC agent and supervised for Anti-Money Laundering. This means our business processes, and the people behind them, meet strict HMRC standards.

Approved Software Provider

We’re an approved software provider and presenter for Companies House, so you and your accounts are in expert hands.

FAQ

Your CT600 questions answered

Do I need to install any software to file my CT600?
No. Easy Digital Filing is a cloud-based service, so there's nothing to download or install. You simply register, log in, and file your CT600 directly through your browser.

What do I need before I start filing my CT600?
You'll need to be registered with HMRC for Corporation Tax online filing, which gives you a username, password, and your company's UTR (Unique Taxpayer Reference). You'll also need your income and expenditure records for the accounting period.

Can I file both my CT600 and iXBRL accounts together?
Yes. When you search for your company using the Quick Start feature, you can choose to file a CT600, iXBRL accounts, or both. Most companies need to submit both together.

Does the software work for micro and small companies?
Yes. During setup you select whether your company qualifies as a micro or small entity, and the templates adjust accordingly.

What sections of the CT600 are covered?
The CT600 filing covers all standard sections, including R&D tax credits, other income, property income, chargeable gains, capital allowances, losses, and loans to participants.

How does the corporation tax calculation work?
As you enter your turnover, expenses, allowances, and reliefs, the built-in calculation engine works out your corporation tax liability in real time, so you can see the impact of your entries as you go.

Does the system check for errors before I submit?
Yes. A built-in validator checks your entries against HMRC's CT600 and accounts production rules as you go. Any errors or warnings are flagged, and you can click through directly to the relevant field to fix them.

How are my accounts converted to iXBRL?
Once you click "Ready to File," your accounts are converted to iXBRL format instantly. You can then use the built-in iXBRL viewer to check exactly which fields have been tagged before submitting.

Can I attach supporting documents to my submission?
Yes. If you have supporting documentation, you can drag and drop it to accompany your CT600 submission to HMRC.

What happens after I submit my CT600?
Once submitted, your CT600, tax computations, and iXBRL accounts go directly to HMRC. You can then download copies of everything for your own records.

Why easy digital filing?

No complicated downloads, just simple online tools built for business owners.

Intuitive & Guided

Step-by-step forms make entering your figures straightforward — you don’t need accounting experience.

Direct Submission

Once ready, file straight to HMRC (and Companies House if accounts are included) with one click — and download your official receipts immediately.

Instant Tax Calculations

Your Corporation Tax liability is calculated as you enter your information — so you always know what you owe (or what refund you might receive).

Ready to File Your Corporation Tax?

Get started today with our secure online platform — and file your CT600 the quick and compliant way.

Start your CT600