The authentication code is a 6 digit alphanumeric code issued to each company by Companies House just after you incorporate your company. The code is used to authorise information filed online and is the equivalent of a company officer's signature.
You’ll need a code to file using Companies House online services or third-party software. Don’t wait until you’re due to file to request your code and risk it being too late - codes are sent to the company by post and can take up to 5 days to arrive. You will find the authentication code on a letter from Companies House such as below:
If you don't have a code you can request your code, Request your code now - it’s sent by post to the company’s registered office and can take up to 5 days to arrive. If you’re new to the service, you’ll need to:
Select ‘Request an authentication code’.
Enter your company registration number.
Select ‘Request code’.
Your code will be sent by post to your company’s registered office - if your company already has a code, a reminder will be sent to you. Allow up to 5-7 days for delivery of your code.