Companies House Authentication Code
Companies House Authentication Code
Your Companies House authentication code is a unique 6-character code used to authorise online filings for your UK company. Here's how to find it, request a new one and use it correctly.
Quick answer: the authentication code belongs to your company rather than you personally. It is different from the 11-character Companies House personal code used for identity verification.
Keep it secure. Your accountant may need it when filing documents on your company's behalf.
What is a Companies House authentication code?
A Companies House authentication code is a unique 6-character alphanumeric code used to authorise online filings for a UK company or LLP. It acts as the electronic equivalent of a company officer's signature and is commonly needed when filing accounts, confirmation statements and changes to company information online.
The code belongs to the company, not the individual. It is different from the Companies House personal code issued to an individual after identity verification.
Why do I need a Companies House authentication code?
Your company authentication code confirms that you are authorised to submit information electronically for the company. You will normally need it when filing through Companies House online services or compatible commercial filing software.
Your accountant may also need your authentication code if you authorise them to submit Companies House filings for your company.
How to get a Companies House authentication code
If you do not know your company's authentication code, you can request it through Companies House. The process is straightforward, but it is important to request it well before a filing deadline.
Sign in
Access the relevant Companies House online filing service and sign in or create the required sign-in details.
Select your company
Enter your registered company number and follow the instructions to request the company authentication code.
Request the code
Companies House will arrange for the authentication code, or a reminder of the existing code, to be sent by post.
Allow for delivery
The code is normally sent to the company's registered office. Allow up to 10 working days for it to arrive.
Can the authentication code be sent to a director's home address?
In certain circumstances, Companies House allows a company's authentication code to be posted to an active officer's home address rather than the registered office. This can be useful if you cannot access mail delivered to the registered office.
The service has eligibility conditions. For example, it cannot generally be used where the company has filed a document online within the previous 30 days, is dissolved, is not based in the UK, or is not an eligible limited company or LLP.
Make sure Companies House holds the officer's current residential address before relying on this option.
Authentication code vs Companies House personal code
These two codes perform different functions and should not be confused. Following the introduction of Companies House identity verification, a director may need both.
Company Authentication Code
- 6-character alphanumeric code
- Belongs to the company
- Used to authorise online company filings
- Can be shared with a trusted accountant filing for the company
- Different companies have their own authentication codes
Companies House Personal Code
- 11-character personal code
- Belongs to the individual
- Issued after successful identity verification
- Used to connect a verified identity with company roles
- The same personal code can be used for multiple appointments
| Feature | Authentication Code | Personal Code |
|---|---|---|
| Belongs to | The company | The individual |
| Length | 6 characters | 11 characters |
| Main purpose | Authorise company filings | Confirm identity verification |
| Can an accountant need it? | Yes, if filing for the company | It may need to be provided when completing relevant filings |
| One code for several companies? | Each company has its own code | The individual's code can apply across their appointments |
Keep your Companies House authentication code secure
Companies House recommends treating the authentication code with the same care as a bank card PIN. Someone with access to the code may be able to submit changes to your company's information.
How to change a Companies House authentication code
You can change or cancel a company's authentication code through Companies House WebFiling. You might want to change the code if it has been disclosed to somebody who should no longer have access, such as a former employee, previous accountant or former company officer.
Once the authentication code has been changed, anyone filing for the company will need the new code. Make sure your current accountant or authorised filing agent is told about the change.
Companies House authentication code not working?
Allow up to 10 working days. Check that the company's registered office details are correct and consider whether the home-address request service is available to you.
Request the company's authentication code again through the appropriate Companies House online service. A reminder can be sent by post.
Check whether the company authentication code has recently been changed. The previous code stops working after a change.
A Companies House personal code does not replace the company authentication code. The two codes serve different purposes.
Check whether you qualify to request delivery to an active company officer's home address instead.
Request the code immediately, but remember that ordering a code does not extend your statutory filing deadline.
Can I give my Companies House authentication code to my accountant?
Yes. You can give the authentication code to a trusted accountant or authorised agent when they need it to file information with Companies House on your company's behalf.
This is common when an accountant prepares and submits statutory company accounts. The code should only be shared with a person or organisation you trust, and you should change it if somebody who previously had authority to file for the company should no longer have access.
If you need help preparing and submitting your statutory accounts, see our company accounts filing service. We can prepare the accounts, corporation tax return and associated filings for eligible owner-managed limited companies.
Companies House authentication code FAQs
How many characters is a Companies House authentication code?
How do I find my Companies House authentication code?
How long does a Companies House authentication code take to arrive?
Can Companies House email my authentication code?
Is my authentication code the same as my Companies House personal code?
Does every director have a different authentication code?
Can my accountant use my company authentication code?
What should I do if someone else knows my authentication code?
Can I file company accounts without an authentication code?
Does requesting a new authentication code extend my filing deadline?
Need to File Your Company Accounts?
The Online Accountants provide fixed-price accounts and corporation tax filing services for UK limited companies. If you already have your Companies House authentication code, we can use it to submit the relevant Companies House filing on your company's behalf.