12 Common CT600 Mistakes That Cost Directors Money (And How to Avoid Them)
Filing your own CT600? Avoid these 12 costly mistakes that catch first-time filers. From wrong accounting periods to missed reliefs — save time and tax.
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Plain-English guides to UK Corporation Tax and CT600 filing.
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How to Amend a CT600 Tax Return: Correcting Mistakes After Filing
Made an error on your CT600? Learn how to amend your corporation tax return within the 12-month deadline, what changes HMRC allows, and the step-by-step process.
Best Alternatives to HMRC's Free Filing Service in 2026
HMRC's free CT600 filing tool closes March 2026. Compare the best alternatives: Taxpipe (£59), accountants, and full accounting software for UK limited companies.
HMRC Free Filing Has Closed: What to Use Instead
HMRC's free CT600 filing service closed on 31 March 2026. Step-by-step guide to choosing a replacement and filing your Corporation Tax return.
CT600 Deadline: When to File Your Corporation Tax Return (and When to Pay)
When is your CT600 due? Filing deadlines, payment deadlines, and how they differ from Companies House deadlines. Avoid late penalties.
iXBRL Tagging for Company Accounts and CT600: What You Need to Know
How iXBRL tagging works for CT600 filing — what gets tagged, HMRC requirements, common tagging errors, and how to generate iXBRL accounts without specialist software.
Corporation Tax Deadlines 2026: When You Need to File and Pay
All corporation tax deadlines for 2026 — CT600 filing dates, payment due dates, and penalties for late filing. Key dates for UK limited companies.
The Cheapest Way to File Your CT600 in the UK (2026)
Compare every option for filing your CT600 — from accountants to DIY software — ranked by cost. Find the cheapest way to file your company tax return.
Taxfiler vs Taxpipe: How They Compared (Taxfiler Now Discontinued)
Taxfiler was discontinued in March 2025. See how the two CT600 tools compared on price, features, and ease of use — and why Taxpipe is the natural replacement for directors filing their own returns.
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.
Close Company Rules & Corporation Tax Explained
Is your limited company a close company? Learn what it means for corporation tax, S455 tax on loans, and how it affects your CT600 filing.
Accountant vs DIY CT600 Filing: Honest Comparison
Should you pay an accountant or file your CT600 yourself? An honest comparison of costs, time, risks, and when each option makes sense for UK limited companies.