CT600 Filing Agent Authorisation with HMRC
How to authorise an agent to file your CT600. Step-by-step guide to HMRC agent authorisation for corporation tax — online, by post, and what to do if things go wrong.
Plain-English guides to UK Corporation Tax and CT600 filing.
How to authorise an agent to file your CT600. Step-by-step guide to HMRC agent authorisation for corporation tax — online, by post, and what to do if things go wrong.
How does corporation tax work for investment companies? Guide to holding investments through a limited company — dividends, capital gains, property, and filing your CT600.
Complete history of UK corporation tax rates from 1965 to 2026. See how rates have changed, key reforms, and what current rates mean for your limited company.
Compare filing your CT600 through HMRC online vs commercial software. Learn the pros, cons, costs, and which option saves you time and money in 2026.
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.
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.
Trading losses, non-trading deficits, capital losses — learn the different types of company loss, how each is relieved, and where they go on your CT600.
How does marginal relief work for UK corporation tax? Plain-English explanation of the 19%-25% band, the formula, worked examples, and how to claim on your CT600.
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.
Complete guide to allowable limited company expenses for Corporation Tax. Covers office costs, travel, staff, professional fees, and what HMRC disallows.
Full 2026 calendar of Corporation Tax deadlines — CT600 filing dates, payment due dates, penalty dates, and quarterly instalment dates month by month.
How goodwill and intangible assets are treated for Corporation Tax. Covers amortisation, writing-down allowances, rollover relief, and CT600 reporting.