Home / Questions / How Do I Register a Company for Corporation Tax?
Last updated 23 October 2026. Written by the Limited Company Accountant UK team, part of Accotax. Figures are for the 2026/27 tax year; always check GOV.UK for the latest rates.
Short answer: Companies House tells HMRC when you incorporate, but you must register for Corporation Tax within three months of starting business activity. HMRC then sends a UTR and activates your online company tax account.
At a glance
| Deadline | 3 months from starting activity |
|---|---|
| Receive | UTR and activation code by post |
| Account | HMRC online company tax account |
What you need
Company number, start date of activity, accounting period end and trading details.
After registering
Keep your UTR safe, set up the online account and diarise the first filings.
Want this handled for you?
Fixed monthly fee, named accountant, free first consultation. Get a free quote or call 0203 4411 258.
The bottom line
Companies House tells HMRC when you incorporate, but you must register for Corporation Tax within three months of starting business activity. If you would rather not do it alone, our fixed fees start at £45.83 + VAT a month.
Frequently asked questions
Do I need a UTR?
Yes, for filing and paying Corporation Tax.
What if I miss the deadline?
You can face penalties, so register as soon as you start.
Ready for a fixed monthly price?
Our packages start at £45.83 + VAT and cover accounts, tax and deadlines. Get a free quote or call 0203 4411 258.
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