The Company Authentication Code: What is it?

Everything you need to know about the Company Authentication Code

The company authentication code is a six digit code issued by Companies House (the UK’s registrar of companies) that allows you to file documents online for your company. Without the code all updates to your company, such as director appointments and resignations, would need to be made via paper documents – an arduous process when compared to the online equivalent.

All companies that are formed online, whether it’s directly with Companies House or through a company formation agent (like Company Formation MadeSimple) are automatically given a company authentication code. If you form with Companies House this will be sent by regular mail to the registered office, normally within a week of formation. If you form with us you’ll be able to access your code online as soon as your company has been formed.

Whilst the initial code is a random selection of numbers and letters, it can be changed directly through the Companies House website to something more memorable if you wish. Because the code is essentially a password it should be picked carefully and treated with care. If the code were to fall into the wrong hands, serious damage could be done to a company. For example, directors could be resigned and news ones appointed, the registered office could be altered, shares could be added and so on. If you ever believe your code has been compromised contact the Companies House fraud team immediately.

A company’s code can change without a director’s permission for one of two reasons:

  • If mail sent by Companies House to the company’s registered office is returned to sender on multiple occasions
  • If it is entered incorrectly on the Companies House site three or more time

If your company’s code has changed for one of the above reasons, or if you have simply misplaced it, you can request a new code. To do this:

  1. Register for Companies House ‘WebFiling’ if you haven’t yet done so
  2. Login to ‘WebFiling’
  3. Select ‘Request an authentication code’
  4. Provide your company’s place of incorporation and company number
  5. The code will then be posted to the registered office

Ready to start your business adventure? Company Formation MadeSimple have registered over 500,000 UK limited companies and offer a number of low cost online formation services for first-time formers and serial entrepreneurs alike. Find out more now: Company Formation MadeSimple


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