> For the complete documentation index, see [llms.txt](https://docs.numble.co.uk/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.numble.co.uk/getting-started/company-unique-tax-reference-utr.md).

# Company Unique Tax Reference (UTR)

Every company has a Unique Tax Reference

When you set up your limited company, HMRC will post your Corporation Tax UTR to the company’s registered address. You may also receive a CT600 notice (a letter reminding you to file your company tax return) that includes the same code.

<figure><img src="https://3849893011-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FPKVkrVCDo9Snh6oEf2hZ%2Fuploads%2FWwZIKDNtQ6qeMeaeI29J%2Fimage.png?alt=media&amp;token=291a0359-fc8f-4b16-a0d7-02927727a1cd" alt="" width="300"><figcaption></figcaption></figure>

### **What the UTR is for**

Your company UTR is a 10-digit number that identifies your business for Corporation Tax purposes.\
We’ll need this code to file your company’s tax returns with HMRC.

Keep it confidential - it should only be shared with your accountant or HMRC.

You may also have a separate personal UTR for Self Assessment. Make sure not to confuse the two.

### If you haven’t received it

You can request a copy of your company’s UTR from HMRC [online](https://www.tax.service.gov.uk/ask-for-copy-of-your-corporation-tax-utr). HMRC will post it to the business address registered with Companies House.


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