Companies House guide

How to get or replace a Companies House authentication code

Companies House sends authentication codes by post, so directors should request or replace the code well before a filing deadline.

Last reviewed: 18 July 2026
Sources checked: 18 July 2026
Reading time: 5 minutes

Written by Business Sorted editorial team

Business Sorted provides general educational information and organisation tools. It is not Companies House, HMRC, a solicitor, an accountant, a tax adviser or a regulated professional adviser. Check official sources and get professional advice where your circumstances need it.

Direct answer

To get a company authentication code, sign in or create Companies House WebFiling access and follow the request steps. Companies House sends the code by post, normally to the registered office, and says it can take up to 10 working days to arrive.

Key facts

Companies House sends company authentication codes by post, not email.
Delivery can take up to 10 working days.
The code is normally sent to the registered office.
A home-address request service exists for active officers in certain circumstances.

Requesting the code

Companies House guidance says you need to create an account or sign in to WebFiling and follow the steps to request the company authentication code.

If the company already has a code, Companies House says it will send a reminder. The code is not sent by email or given over the phone.

Where the code is sent

Companies House normally sends the authentication code by post to the company’s registered office. The guidance says it can take up to 10 working days to arrive.

If you cannot access the registered office, Companies House provides a service to request the code to be sent to an active officer’s home address in certain circumstances.

If the code does not arrive

If the code was sent to the registered office and has not arrived, check whether the registered office address on the company register is correct. If it is wrong, you may need to correct the address before requesting the code again.

If a deadline is close, check official Companies House help rather than guessing. Code delivery time is a practical reason to organise access well before accounts or confirmation statement dates.

Frequently asked questions

Can Companies House tell me the code over the phone?

No. Companies House guidance says it cannot send the code by email or tell you the code over the phone.

Can I request the code on the deadline day?

You can request it, but it may not arrive in time. Companies House says delivery can take up to 10 working days.

Useful next steps

Keep company updates organised

Keep important company updates and responsibilities organised. BusinessSorted helps you see the tasks that need your attention.

Relevant feature: Filing access preparation reminders.

Start setup Companies House resources