A Company Authentication Code is a unique password issued to all Limited Companies.

It is highly confidential so if you have lost your Company Authentication Code you won’t be able to retrieve it by phone.

What is a Company Authentication Code

A Company Authentication Code is made up of 6 characters issued by Companies House to every Limited Company on its register, whether it is trading or dormant.

It is needed every time a change is made to the ownership, control or Directors of a Limited Company.

Before online filing was available at Companies House, any changes to a Company needed to be done on paper forms and signed by Directors.

With the move towards online filing, the Company Authentication Code was launched to replace a Directors’ physical signature.

Therefore it is considered to be the equivalent of a Directors signature, making it a really important piece of information.

Where to Find Your Company Authentication Code

Once you have formed your Limited Company, you’ll need to make a request for your code, separately.

If you haven’t requested it, then you need to do so now. Don’t delay – you’ll need it every time you want to make a change to your Company online.

You can request it by signing up to Companies House Online here. It can take up to 5 days to arrive and will be posted to your Registered Office Address.

To set yourself up on Companies House online and request your Company Authentication code:

  1. Go to Companies House Online

  2. Register your email address and password.

  3. Select ‘Request an authentication code’.

  4. Enter your company registration number.

  5. Select ‘Request code’.

How to Find a Lost Company Authentication Code

If you have already requested your Company Authentication Code but have lost it, you won’t be able to retrieve it by phone.

Due to the importance of the code, Companies House can only send your code out by post to your Registered Office Address.

The easiest way to get a copy of your authentication code is to go online and request a copy by logging onto your Companies House online account and clicking “Request an Authentication Code”

You’ll need to your Registered Company Number (which is publicly available on the Companies House website).

If you have any questions, then you should call Companies House on 0303 123 4500.

You Company Authentication Code is important to your day to day Company administration, here’s how to change it to something more memorable.

Anita Forrest

Anita is a Chartered Accountant with over a decade of experience taking self-employed business owners from financially confused to business savvy.
She is the creator of the ‘Go Self Employed’ website, which is her corner on the internet where she makes self-employment less terrifying.
Anita Forrest

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