CORPORATION TAX

If you trade through a limited company, you are legally required to pay Corporation Tax on your taxable profits. Unlike self-assessment for individuals, Corporation Tax has its own unique rules, deadlines, and filing requirements—and getting it wrong can trigger automatic penalties, interest charges, and even HMRC enquiries.

At Accountancy and Tax Crew, we take the complexity out of Corporation Tax. From calculating your liability to filing your CT600 return and advising on legitimate reliefs, we ensure your company stays compliant while paying no more tax than necessary.

What Is Corporation Tax?

Corporation Tax is a tax on the taxable profits of UK limited companies, foreign companies with a UK branch or office, clubs, societies, associations, and other unincorporated bodies that trade for profit.

Corporation Tax Deadlines: Critical Dates

Missing a Corporation Tax deadline is expensive.

Deadline	What Is Due	Penalty for Late Filing/Payment
9 months and 1 day after your accounting year end	Payment of Corporation Tax due	Interest charged from day 1. Additional penalties apply for continued late filing.
12 months after your accounting year end	Filing of CT600 tax return	£100 initial penalty, increasing to £1,600+ for persistent lateness.

How We Help with Corporation Tax

1. Year-End Corporation Tax Computation

We prepare a full CT600 return (Corporation Tax return) based on your company’s annual accounts. This includes:

• Calculation of trading profits (after allowable expenses)
• Adjustment for disallowable expenses (e.g., client entertaining, depreciation)
• Capital allowances claim (instead of depreciation)
• Relief for qualifying charitable donations
• Calculation of Marginal Relief (if applicable)
• Capital Gains Tax on any asset disposals

2. Claiming Reliefs & Deductions

Corporation Tax is charged on taxable profits, not accounting profits. We ensure you claim every legitimate relief to reduce your liability.

Relief

• Capital Allowances
• Full Expensing (100% first-year allowance)
• Annual Investment Allowance (AIA)
• Research & Development (R&D) Relief
• The Patent Box
• Creative Industries Reliefs
• Loss relief
• Charitable donations

3. Payment Planning & Cash Flow Management

Corporation Tax is typically the largest single tax bill a company pays. We help you plan ahead:

• Quarterly estimates of your likely liability
• Ring-fencing profits in a separate savings account
• Director loan account planning to time dividend extraction around tax payments
• Payment arrangements with HMRC (Time to Pay) if cash flow is tight

4. Filing & Compliance

We handle the entire filing process:

• Prepare and file CT600 electronically
• Submit supporting computations and accounts (where required)
• Track filing and payment deadlines with automated reminders
• Respond to any HMRC enquiries or information requests

5. Year-Round Planning

Corporation Tax is not just a year-end exercise. We advise throughout the year on:

• Timing of major purchases (to maximise capital allowances in the right tax year)
• Director remuneration planning (salary vs. dividends vs. pension contributions)

Common Corporation Tax Mistakes

Mistake                                                                                               Consequence

Confusing accounting profit with taxable profit                    Overpaying tax (by not claiming deductions) or underpaying (by claiming disallowable expenses)

Missing the 9-month payment deadline                                  Automatic interest charges, even if you file on time

Failing to file CT600 by 12 months                                            £100 penalty initially, escalating to daily penalties and public record of non-compliance

Not claiming capital allowances                                                  Paying tax on profit that includes depreciation (which HMRC does not allow)

Why Choose AT Crew for Corporation Tax?

Specialist Limited Company Knowledge

We work exclusively with limited companies, partnerships, and sole traders. We are not generalist accountants—we specialise in the specific needs of incorporated businesses.

Proactive, Not Reactive

We don’t just calculate your tax bill after year end. We advise you before the year ends on actions you can take to reduce it.

HMRC Enquiry Support

If HMRC opens a Corporation Tax enquiry into your return, we represent you throughout. Our fees for enquiry work are transparent and agreed upfront.

---

Running a limited company?

Let us ensure your Corporation Tax is accurate, compliant, and optimised.