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How do I register for Corporation Tax?

Corporation tax is a tax on the profits of limited companies and some other organisations (for example clubs, societies, associations and charities). It is self–assessed which means it is up to the company (not HM Revenue and Customs) to work out how much corporation tax is payable.

When do I need to register for Corporation Tax?

The owners of a business may decide to form a company at any time. Once you’ve registered your company with Companies House you will need to register it for Corporation Tax. A company needs to register within three months of any business activities starting. You may get a penalty if you register late.

How can I register for Corporation Tax?

When the decision has been made to become a company, the first step is to register with Companies House.

In order to register, either:

Once Companies House has approved the company, a certificate of incorporation will be issued. This will show the date of incorporation and the company registration number (which is unique).

Companies House will inform Her Majesty’s Revenue and Customs (HMRC) of the formation of a new company.

HMRC will send a letter to all newly formed companies. The letter will include the company’s 10-digit Unique Taxpayer Reference (UTR).

The company must register for corporation tax (the tax paid by companies) online within three months of any business activities starting.

Corporation Tax calculator

Use our handy interactive calculator to work out how much Corporation Tax you'll pay.


Please note the results on the screen are estimates only. 

Please note the results on the screen are estimates only. 

Checklist: What information will I need?

The information needed to register for corporation tax with HMRC is listed below. Login to save this checklist to your profile for future use – as you work through the list, any checkboxes that are ticked or unticked will be automatically saved to your profile. (To register to join and enjoy the benefits of membership click on the link at the top right of the page. It will only take a few minutes to create your profile).

You must be logged in to use this checklist

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What records do I need to keep?

A limited company must keep details of:

  1. Annual accounts, including profit and loss (income statement)
  2. Bank statements, paying in slips, cheque books and details of amounts paid or received electronically
  3. Cash books and other account books
  4. Purchase and sales invoices
  5. Credit or debit notes (issued or received)
  6. Order and delivery notes
  7. Records of daily takings
  8. Payroll records
  9. VAT records
  10. Any relevant business correspondence.

When will I first pay Corporation Tax?

Any corporation tax due must be paid electronically by nine months and a day after the accounting period end.

For example – a company with a year-end 31 December 2018 must pay any corporation tax due by 1 October 2019.

You can calculate when yours is due using our interactive Corporation Tax deadline calculator. 

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