Before You Log In — Find Your Authentication Code
Before you jump into the Companies House WebFiling (EWF) portal, you'll need your Company Authentication Code. Think of this as your company's "master password" — a 6-character alphanumeric code issued when your company was first incorporated.
You should never give this code to anyone except a trusted adviser.
Can't Find Your Code?
If you've lost that original letter from when you set the company up, don't panic. Here's how to get a new one:
Companies House will post the new code to your company's registered office address, usually within 5 working days.
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Common Questions
What is a Company Authentication Code?
It's a 6-character alphanumeric code issued by Companies House when your company is first incorporated. It acts as your company's master password for filing online.
Who should I share my authentication code with?
Only share it with a trusted adviser, such as your accountant or company secretary. Never give it to anyone you don't fully trust.
How long does it take to receive a new code?
Companies House will post a new code to your registered office address. It typically arrives within 5 working days.
Can I request my authentication code online?
Yes. Log into the Companies House WebFiling portal, enter your company number, and click 'Request an authentication code'. The new code will be sent by post to your registered office.