Articles on: Registered Address

Where is my Company Authentication Code!

⚡ Quick Answer: Your Company Authentication Code is sent by post from Companies House to your registered office address. If your registered office is with Hoxton Mix, the letter will be scanned and available under the Mail tab in your customer portal when it arrives. Allow 5-10 working days from the request.



How to Request a New Code


  1. Go to Companies House WebFiling and sign in (or register if you haven't)
  2. Select "Forgotten your authentication code?"
  3. Choose whether the code is for a company or LLP
  4. Enter your company number and click Submit
  5. Confirm your details


The code will be posted to your registered office address.


💡 Tip: You can also request the code be sent to a director's home address if the officer's address is on file at Companies House.



If Your Registered Office Is With Hoxton Mix


The authentication code letter will be:

  • Received at 66 Paul Street, London EC2A 4NA
  • Scanned on the day it arrives
  • Available under the Mail tab in your customer portal, with a notification


If the letter hasn't appeared in your portal yet, it usually means it hasn't arrived from Companies House. Allow 5-10 working days.


⚠️ Important: If your subscription is inactive, mail will be returned to sender. Make sure your account is active before requesting the code. If mail was returned, contact Companies House to request a new code.



What You'll Need


  • Your company number
  • A Companies House WebFiling account (this is different from a standard Companies House account)



Why Is It Sent by Post?


Companies House sends authentication codes by post only — not by email. This is a security measure to prevent unauthorised access to company filings.



Common Questions


How long does it take to arrive?

Usually 5-10 working days from the date you request it.


I can't see it in my portal — what should I do?

If it hasn't appeared, it likely hasn't arrived yet. Check back in a few days. If it's been more than 10 working days, request a new code from Companies House.


Can I get the code by email instead?

No. Companies House only issues authentication codes by post for security reasons.


Can it be sent to my home address instead?

Yes — use the alternative request form if you want it sent to a director's residential address on file.



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Updated on: 28/03/2026