---
title: Corporation Tax explained
description: Registering for Corporation Tax
---
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1. [After Company Registration](https://help.rapidformations.co.uk/after-company-registration?hsLang=en-gb)
2. [Register for Corporation Tax](https://help.rapidformations.co.uk/after-company-registration/register-for-corporation-tax?hsLang=en-gb)
# Corporation Tax explained
## When and how to register for Corporation Tax with HMRC
### When to register for Corporation Tax
You must register your company for Corporation Tax with HMRC within 3 months of starting business activities.
“Starting business activities” can include:
- Trading or selling goods/services
- Buying or selling assets
- Earning interest
- Hiring employees
- Advertising or promoting your business
### What if your company is dormant?
If your company is not trading and has no significant accounting transactions, it may be considered dormant. In this case, you should inform HMRC that your company is dormant, and you may not need to register for Corporation Tax until trading begins. This can be done online [here](https://www.gov.uk/tell-hmrc-your-company-is-dormant-for-corporation-tax).
### How to register for Corporation Tax
You can register online by [adding Corporation Tax services to your business tax account](https://www.gov.uk/limited-company-formation/add-corporation-tax-services-to-business-tax-account). Before you begin, make sure you have the following information ready:
- Your company’s [Unique Taxpayer Reference](https://help.rapidformations.co.uk/after-company-registration/unique-taxpayer-reference-utr-number?hsLang=en-gb) (UTR)
- Company registration number (find this by searching your company name [here](https://find-and-update.company-information.service.gov.uk/))
- Date your company started trading
- Your accounting period dates
- Details of your business activities
Once registered, HMRC will confirm your Corporation Tax obligations and deadlines.
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