Authentication code (webfiling)
What is the authentication code? An authentication code is a 6 digit alphanumeric code issued by Companies House to each UK-registered company. It is sometime also known as the webfiling code. It is a bit like a company’s password for their Companies House account.
The authentication code is used to access webfiling (for direct filings at Companies House) and to authorise Kudocs to access and use the company’s information stored at Companies House. Kudocs needs this code and this information to create a Kudocs account and enable automatic filing by Kudocs at Companies House on your behalf.
You need to enter your authentication code to onboard a UK-registered company to Kudocs. Once you have onboarded a company, or incorporated a new company, you should not need the authentication code again: all your filings can be done via Kudocs without having to use the authentication code (or webfiling).
If you incorporate an entity using Kudocs, as soon as the company is incorporated, the authentication code will be saved in the company settings in Kudocs. Companies House will also send the code by post to the registered address of the company, but that might take a while to arrive.
Where do I find my authentication code? The authentication code is stored in Settings > Company and can be seen by Admin users only. The authentication code is always stored in Kudocs, so it is easy to find at any time.
If you don’t have a copy to hand, you can order a new one from Companies House here.
Where does Kudocs store the authentication code? The authentication code is stored in Settings > Company and can be seen by Admin users only.
How do I get my authentication code when I incorporate a new company? If you incorporate a company using Kudocs, the authentication code is automatically stored in Settings > Company. It will be stored in Kudocs immediately upon incorporation (so there is no need to wait for any letter from Companies House) and can be seen by Admin users only. The company will also be sent the authentication code by Companies House by post, but it will always be stored in Kudocs, so it is easy to find at any time.
How do I change my authentication code? You will need to login to Companies House and request them to change authentication code.
My authentication code has changed, how do I update Kudocs (change my authentication code in Kudocs)? Once you have your new authentication code, if you have admin permissions you can log in to your company account go to Settings and change the authentication code (portfolio customers only).
Last updated: 26/06/2026 by Kudocs Admin