# Company Unique Tax Reference (UTR)

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="/files/1wAb2f5x2McYVVuzOlJP" 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.


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.numble.co.uk/getting-started/company-unique-tax-reference-utr.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.