Payment comes before filing
Corporation Tax Registration & Returns in the United Kingdom
The UK gives you twelve months to file a corporation tax return but only nine months and a day to pay it.
GCC business setup specialists
Two deadlines, in the wrong order
Corporation tax is payable nine months and one day after the end of the accounting period, while the return itself is not due until twelve months after it. Companies that treat the filing deadline as the date that matters are already three months late on payment and accruing interest. Knowing the tax figure early is therefore a cash-flow requirement, not an accounting nicety.
- Both deadlines diarised, with the payment date treated as the real one
- Marginal relief and associated companies assessed properly
- Tax figure estimated early so you can fund it
20+
Mainland, free zone and offshore jurisdictions we file in — so the recommendation is based on your activity, not on which authority we happen to be registered with.
7,000+
Companies successfully established.
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What applies
The UK corporation tax picture
Rate depends on profit level and group structure.
| Element | Position |
|---|---|
| Scope | Profits of a UK resident company, worldwide. |
| Main rate | Applies above the upper profit threshold. |
| Small profits rate | A lower rate below the small profits threshold. |
| Marginal relief | Tapered rate between the two thresholds. |
| Associated companies | Divide the thresholds, raising your effective rate. |
| Payment | Nine months and one day after the period end. |
Rates, thresholds, the associated company rules and instalment payment requirements are set by HMRC and change at Budget. Yours are confirmed against the rules in force for your accounting period.
How it works
Getting corporation tax right
Estimate early, file accurately.
01
Register and set the cycle
Registration with HMRC within the required period, accounting period confirmed and both deadlines diarised.
02
Estimate before you owe
The liability estimated ahead of the payment date, with associated companies and marginal relief factored in so the figure is realistic.
03
File the return
Return prepared from the statutory accounts and filed with the computations, with any claims and reliefs included.
- Accounting period dates
- Statutory accounts or trial balance
- Any other companies under common control
- Shareholdings and group structure
- Expected profit for the period
- Capital expenditure in the period
- Research and development activity, if any
- Loans to or from directors
- Dividends paid in the period
- Losses brought forward
- Prior returns and HMRC correspondence
- Government Gateway access or authorisation
Scope
What is included, and what is not
Stated plainly, so nothing is added once the engagement starts.
Included in the service fee
- Corporation tax registration with HMRC
- Both deadlines diarised with reminders
- Associated company and marginal relief assessment
- Liability estimate ahead of the payment date
- Return and computations preparation
- Filing with HMRC
- Claims and reliefs identified
- Correspondence with HMRC on routine matters
Not included, quoted separately
- The tax itself, paid at cost
- Interest and penalties for earlier periods
- Statutory accounts preparation unless included
- Audit where required
- Research and development claims, quoted separately
- Transfer pricing studies
- Enquiry defence beyond routine correspondence
- Personal tax returns for directors
Verify independently
Relevant UK authorities
We file directly with these bodies on your behalf.
Companies HouseHM Revenue & CustomsFinancial Conduct AuthorityInformation Commissioner’s OfficeIntellectual Property OfficeInsolvency Service
Questions
UK corporation tax — FAQs
When is UK corporation tax actually due?
Nine months and one day after the end of your accounting period — three months before the return deadline. That ordering catches out most new companies.
What are associated companies?
Broadly, companies under common control. They divide the rate thresholds between them, which can push a small company onto a higher effective rate. It is frequently overlooked in group structures.
Do I have to register for corporation tax?
Yes, with HMRC, within the period required after the company becomes active. Incorporating at Companies House does not do it for you.
What if my company is dormant?
You may still need to notify HMRC and may receive a notice to file. Dormancy has to be managed rather than assumed.
Are quarterly instalments ever required?
Larger companies pay by instalment rather than in a single sum. We confirm whether that applies to you before the first payment date.
Go deeper
More United Kingdom services
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