How to File CT600 Online in 2026: Complete Step-by-Step Guide
HMRC's free filing service closed on 31 March 2026. Here's exactly how to file your CT600 corporation tax return online in 2026 — step by step, with tips and common mistakes to avoid.
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Plain-English guides to UK Corporation Tax and CT600 filing.
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HMRC Free CT600 Filing Ended March 2026: What Are Your Options?
HMRC's free Corporation Tax Online service closed 31 March 2026. Here's what changed and the cheapest ways to file your CT600 now that the free option is gone.
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.
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.
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.
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.
UK Corporation Tax Rates: Complete History
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.
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.
HMRC CT600 Online vs Software: Which Is Better?
HMRC's free CT600 online filing service closed on 31 March 2026. Compare what it offered against commercial software, and see what your filing options are now.
Corporation Tax Deadlines Calendar 2026
Full 2026 calendar of Corporation Tax deadlines — CT600 filing dates, payment due dates, penalty dates, and quarterly instalment dates month by month.
How to File Your CT600 Yourself in 2026 (Complete DIY Guide)
File your CT600 without an accountant in 2026. What you need, how to prepare accounts, calculate tax, and submit to HMRC.