CT600 Box-by-Box Guide: Every Core Box Explained (2025/26)
Complete walkthrough of every CT600 box from 1 to 620. Plain English explanations, what to enter, and which boxes most small companies actually use.
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Plain-English guides to UK Corporation Tax and CT600 filing.
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How Are Dividends Taxed for Corporation Tax? A Complete Guide
How dividends interact with Corporation Tax — paying dividends, receiving dividends, the dividend exemption, franked investment income, and CT600 reporting for UK companies.
Do I Need an Accountant for Corporation Tax? When DIY Makes Sense
Find out whether you need an accountant for corporation tax or can file your CT600 yourself. Honest guide for UK limited company directors.
Small Company Corporation Tax Rates 2025/2026: Complete Guide
Understand corporation tax rates for small companies in 2025/2026, including the 19% and 25% thresholds, marginal relief calculation, and associated companies rules.
First Year Corporation Tax: A Complete Guide for New Companies
New limited company? Learn when to register for corporation tax, your first accounting period, filing deadlines, and how to avoid common first-year mistakes.
How to Use HMRC Government Gateway to File Your CT600
Step-by-step guide to setting up and using your HMRC Government Gateway account to file your CT600 Corporation Tax Return online.
Company Formation & Corporation Tax Registration
Step-by-step guide to registering for Corporation Tax after forming a limited company. Covers CT41G, UTR numbers, deadlines, and first CT600 filing.
Corporation Tax for Small Businesses: 2026
Complete 2026 guide to corporation tax for small businesses. Covers rates, allowable expenses, filing deadlines, payment dates, and tips to reduce your tax bill legally.
Corporation Tax on Rental Income: CT600 Guide
How is rental income taxed in a limited company? Learn how property income works on your CT600, allowable deductions, and when a property company makes sense.
Disallowable Expenses for Corporation Tax (Full List)
Which expenses can't you deduct on your CT600? Complete guide to disallowable expenses for corporation tax — entertaining, fines, personal costs, and more.
R&D Tax Credits for SMEs: Complete Guide to Claiming
How UK small and medium-sized companies can claim R&D tax credits. Covers eligibility, qualifying costs, calculation examples, the merged scheme, and how to include R&D relief on your CT600.
Employer NIC: Corporation Tax Deduction Guide
Is employer NIC an allowable deduction for corporation tax? Yes. Learn how employer National Insurance works, current rates, the Employment Allowance, and how to claim on your CT600.