I Don't Have a UTR — Is My Company Registered for Corporation Tax?

What Is a UTR?

A UTR (Unique Taxpayer Reference) is a 10-digit number issued by HMRC when your company is registered for corporation tax. TinyTax requires your UTR to submit a CT600 to HMRC.

Your UTR appears at the top of any HMRC letter about corporation tax — look for a letter titled "Notice to deliver a Company Tax Return" or similar.

Why Might You Not Have a UTR?

Not every limited company automatically receives a UTR. HMRC registers a company for corporation tax when:

• The company notifies HMRC that it has started trading (required within 3 months of starting)
• HMRC identifies the company has potential tax obligations

If your company has never traded and was never formally registered with HMRC for corporation tax, you may genuinely have no UTR.

What to Do If You Have No UTR

Step 1 — Check your records

Search your email and post for any HMRC letter about corporation tax. Your UTR would have been issued in a letter shortly after registration.

Step 2 — Contact HMRC to confirm

Call HMRC's Corporation Tax helpline: 0300 200 3410 (Monday–Friday, 8am–6pm).

Give them your:

• Company name
• Company number (from Companies House)

Ask them to check whether your company is registered for corporation tax and whether a CT600 is required.

If HMRC confirms no CT registration and no filing required: You don't need to file a CT600. The filing reminder shown on your TinyTax dashboard comes from our own system — it's based on your Companies House filing date, not a confirmed HMRC obligation. You can disregard it.

If HMRC confirms you are registered and a return is required: They will confirm or re-issue your UTR. Once you have it, you'll also need a Government Gateway Organisation account enrolled for corporation tax — see our Government Gateway guide for step-by-step instructions.

Dormant Residents Associations and Corporation Tax

Residents associations incorporated as limited companies are sometimes exempt from corporation tax on income derived from mutual trading (collecting service charges from members). However, this exemption depends on the specific circumstances. HMRC will confirm your position when you call.

Common Questions

Does TinyTax send the filing reminders, or does HMRC?

The reminders shown in TinyTax come from our own system and are based on your Companies House accounting period. They are not notifications from HMRC. Only HMRC can confirm whether you have an obligation to file a CT600.

Can I file Companies House accounts without a UTR?

Yes. Companies House accounts and the CT600 are entirely separate filings. Your TinyTax dormant accounts submission to Companies House does not require a UTR — only the CT600 does.

What if I can't reach HMRC?

You can also write to HMRC at: HM Revenue and Customs, Corporation Tax Services, BX9 1AX. Include your company name, company number, and registered address.