Corporation Tax
What tax does my company pay on its profits, and how is it worked out?
Corporation Tax is the tax a UK company pays on its profits. These entries explain how it is worked out, what has to be filed, and when it has to be paid.
Each entry below answers one question and lists the official sources it rests on.
Registering and the UTR
When do I have to tell HMRC my company is active?
When the 3 months to tell HMRC start, what counts as active, and the second 12-month deadline.
Published
Is my company dormant for Corporation Tax, for Companies House, or both?
The two meanings of dormant, how to tell HMRC, and what you still file with Companies House.
Published
Rates, the small profits rate and marginal relief
What rate of Corporation Tax does my company pay?
The 19% and 25% Corporation Tax rates, the £50,000 and £250,000 limits, and what cuts those limits.
Published
What happens if my accounting period crosses 1 April?
Why a year end such as 31 December splits your profit between two financial years, and when that changes your Corporation Tax.
Published
How does marginal relief work?
How marginal relief works out your Corporation Tax when profit is between the two limits, and where the 3/200 comes from.
Published
The tax return and the computation
What is my Corporation Tax accounting period, and why can it differ from my accounts?
What a Corporation Tax accounting period is, when it starts and ends, and why it can differ from the period your accounts cover.
Published
When is my CT600 due, and what goes with it?
The deadline for your Corporation Tax return, when it can be later, and what the return must include.
Published
Paying
When do I pay Corporation Tax?
The date your company's Corporation Tax is due, how to count it, and what happens at weekends.
Published
Associated companies
Does owning another company change my Corporation Tax?
How controlling another company cuts your £50,000 and £250,000 Corporation Tax limits, and which companies count.
Published
From other topics
What are dormant company accounts and who can file them?
What makes a company dormant for Companies House, what dormant accounts contain, and who can use form AA02.
Published
What do micro-entity accounts have to contain?
The balance sheet, profit and loss account, notes and statements that micro-entity accounts must have, and which parts you file.
Published
How are a micro-entity's fixed assets measured, and can it revalue them?
How a micro-entity records equipment and property at cost, depreciates it, writes it down, and treats depreciation for tax.
Published
How should a micro-entity account for intangible assets and goodwill?
How a micro-entity shows bought licences and goodwill, why home-made brands and logos are never assets, and how both are written off.
Published
How do I show a loan between my company and me in the accounts?
How a micro-entity records loans to and from its director, the note it must give, and when a loan to a director brings extra tax.
Published
Why do micro-entity accounts show no deferred tax?
Why a micro-entity's tax line holds current tax only, and what happens when depreciation and capital allowances differ.
Published
How do dividends show in my accounts, and how much can my company pay?
How a dividend reduces a micro-entity's reserves, when it becomes a debt, and how the law limits what your company can pay.
Published
Does a micro-entity have to disclose related party transactions?
Why micro-entity accounts need no related party note, and how to show a loan to a director.
Published
How do going concern and events after the year end affect a micro-entity's accounts?
When accounts assume your company will carry on, and which events after the year end change the figures.
Published
What happens when my company starts or stops using the micro-entity rules?
How to move onto the micro-entity rules, and why one year over the limits does not take you off them.
Published
Can a dormant company use the micro-entity accounting rules?
How a dormant company uses the micro-entity rules, what its accounts say, and when it stops being dormant.
Published
Which expenses can my company deduct?
The "only for the business" test for company costs, how mixed costs are split, and why equipment and dividends are treated differently.
Published
What is the difference between revenue and capital spending?
How to tell a day-to-day cost from capital spending, why it changes your tax, and how repairs, instalments and short-life items are treated.
Published
What is the Annual Investment Allowance and how do I claim it?
How the Annual Investment Allowance takes the full cost of equipment off your profits, what qualifies, and how and when to claim it.
Published
What is full expensing and does it help a small company?
What full expensing gives, what it excludes, why the Annual Investment Allowance usually does the same job, and what happens when you sell.
Published
Can my company deduct my own salary and pension contributions?
When your company can deduct your salary and its pension contributions for you, and the timing rules that decide which year they count in.
Published
What are HMRC's penalties for a late Corporation Tax return?
The fixed penalties for a late Corporation Tax return, the extra penalty on unpaid tax, and when HMRC may let you off.
Published
What happens if I pay Corporation Tax late?
When Corporation Tax is due, how late payment interest is worked out, and what it costs.
Published
In preparation
Nothing is published under these headings yet.
- Losses
Related topics
Every topic in TaxpediaExpenses and allowances
What your company can deduct, and what you can claim as a director.
Deadlines and penalties
The main filing and payment deadlines, and what happens if one is missed.
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These pages explain the rules in general terms. They are not advice about your company's own figures. When something here matters to a decision, check the official source we link to.