Corporation Tax
Services
A limited company pays corporation tax on its profits. The rate is 19% for profits up to £50,000 and 25% above £250,000, with marginal relief tapering between the two — which produces an effective rate of 26.5% on profits in that band. Both thresholds are divided between associated companies, so owning more than one company changes the maths.
Corporation Tax — what it is and who needs it
A limited company pays corporation tax on its profits. The rate is 19% for profits up to £50,000 and 25% above £250,000, with marginal relief tapering between the two — which produces an effective rate of 26.5% on profits in that band. Both thresholds are divided between associated companies, so owning more than one company changes the maths.
The return, a CT600, is due twelve months after your year end, but the tax must be paid nine months and one day after year end. That ordering catches new directors out: the money leaves before the paperwork is due. We tell you the figure as early as we can so it can be put aside.
Most of what reduces a corporation tax bill has to be done before the year closes. Full expensing gives 100% relief on qualifying new plant and machinery, the Annual Investment Allowance covers up to £1m of qualifying expenditure including second-hand assets, and employer pension contributions are deductible in the period they are paid. All of them depend on timing.
There are reliefs worth checking even in small companies. R&D relief is narrower and more heavily scrutinised than it was, but it still applies to genuine technical problem-solving, not just laboratories. Losses can be carried back against the previous year's profits for an immediate refund rather than carried forward. It is worth someone asking the question each year.
Who this is for
Every UK limited company, plus directors weighing up whether the company structure still suits them.
Key facts & deadlines
-
Payment deadline
9 months and 1 day after year end (for companies not in quarterly instalment payments).
-
Return deadline (CT600)
12 months after end of the accounting period.
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Capital allowances
Full expensing available on most qualifying plant and machinery.
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R&D Tax Credits
SMEs can claim enhanced deductions on qualifying research and development costs.
Free consultation — no obligation
Everything included in our
Corporation Tax service
Our all-inclusive service means no surprises — everything you need is handled by your dedicated accountant.
- Corporation tax computation and CT600 filing
- Capital allowances and full expensing claims
- Annual Investment Allowance planning
- Loss relief, carry back and carry forward
- Associated company threshold checks
- Director's loan and section 455 review
- R&D relief assessment where relevant
- A pre-year-end planning conversation
Who our Corporation Tax
service is designed for
Every UK limited company, plus directors weighing up whether the company structure still suits them.
Quick checklist
- Corporation tax computation and CT600 filing
- Capital allowances and full expensing claims
- Annual Investment Allowance planning
- Loss relief, carry back and carry forward
- Associated company threshold checks
- Director's loan and section 455 review
- R&D relief assessment where relevant
- A pre-year-end planning conversation
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How our Corporation Tax service works
We keep it simple. No jargon, no chasing — just a reliable service that runs in the background.
Plan before year end
Equipment, pension contributions and remuneration all have to be decided before the year closes to count.
Compute and check
We prepare the computation alongside your accounts and apply every allowance the company qualifies for.
File and diarise payment
Return filed and the payment date confirmed in writing — nine months and a day after year end.
Common Corporation Tax questions — answered
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19% on profits up to £50,000 and 25% on profits over £250,000. Between those figures marginal relief applies, which produces an effective marginal rate of 26.5% on the profits falling in the band.
Both thresholds are divided by the number of associated companies. If you control two companies, the small profits limit becomes £25,000 each, which frequently surprises people who set up a second company for a side venture.
Nine months and one day after the end of your accounting period. The CT600 return is not due until twelve months after year end, so payment comes first — a common cash flow trap for a company in its first profitable year.
Very large companies pay in quarterly instalments instead, but that only applies well above the profit levels most small companies reach.
The main levers are capital allowances on equipment, employer pension contributions, getting the salary and dividend split right, and making sure every genuine business cost has actually been captured in the accounts. Full expensing gives 100% relief on qualifying new plant and machinery.
Nearly all of it depends on acting before the year end. Once the year has closed, the options that remain are mostly limited to making sure nothing was missed.
Possibly, but the rules have tightened considerably and HMRC scrutinises claims closely. The work must seek an advance in science or technology and resolve genuine technical uncertainty that a competent professional could not readily work out.
Ordinary product development, cosmetic changes and routine software configuration do not qualify. We will give you a straight assessment rather than encouraging a speculative claim, because an unsuccessful one now carries real risk.
Ready to simplify your
Corporation Tax?
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Let's talk about
your business.
Whether you want to switch accountant, need help with a specific return, or just want to know how much you could be saving — get in touch. The first call is always free.
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