This guide explains how to formally gain an extension on the filing deadline, this is not a guide to explain how to change the accounting reference date - which can often lead to an extension in the deadline as a result of the change. 

1. Understand When an Extension Is Possible

Normally, UK companies must file their accounts by the statutory deadline set by Companies House (usually nine months after the accounting reference date for private companies). Extensions are not routinely granted and are only possible under exceptional circumstances (e.g., unforeseen events like illness, fire, flooding, or technical issues).

2. Prepare Your Justification

You should submit a clear explanation for why the company cannot meet the current deadline. Valid reasons typically include:

• Illness affecting key staff
• Bereavement
• Major IT or software failure
• Damage to company records due to fire or flood

Companies House does not grant extensions for reasons such as being busy, lack of reminding, or your accountant being away unless it genuinely prevents filing.

3. Apply Online at Companies House

• Use the Companies House Online Service—you’ll need the company’s registration number and authentication code.
• Complete the online application form, detailing the reason for your request and the extension period needed.
• Submit your application before the filing deadline. Extensions cannot be granted after the accounts are overdue and penalties cannot be avoided by requesting an extension late.

4. Wait for Confirmation

• Companies House will review your request and notify you of their decision. If approved, you will be given a new accounts filing deadline.
• If your request is refused, you will need to file by the original deadline to avoid late filing penalties.