How to File CT600 Online After HMRC Free Service Closed
Step-by-step guide to filing your CT600 corporation tax return online using commercial software after HMRC discontinued its free filing service in March 2026.
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Plain-English guides to UK Corporation Tax and CT600 filing.
CT600 Box-by-Box Guide for Small Companies (2025/26)
Plain English explanation of every CT600 box that matters for a typical small limited company. No jargon, no confusion.
How to File a CT600 for a Dormant Company (Step-by-Step)
Complete guide to filing a dormant company CT600. Even if your company did nothing, you still need to file. Here's exactly how.
What Happens If You Miss Your CT600 Filing Deadline?
Late CT600 filing penalties explained: from 1 April 2026, £200 on day one and £400 at 3 months — doubled from previous rates. Plus 10% tax-geared penalties and 7.75% late payment interest. How to minimise the damage.
HMRC Free CT600 Filing Is Ending March 2026 — What You Need to Do Now
HMRC is closing its free Corporation Tax filing service on 31 March 2026. Here's what this means for your company and the cheapest alternatives.
Corporation Tax Rates 2025/26: Complete UK Guide
All UK Corporation Tax rates for 2025/26 including small profits rate, main rate, marginal relief, and associated company rules. With worked examples.
What Is iXBRL and Why Does Your CT600 Need It?
Plain English explanation of iXBRL — the tagged format HMRC requires for CT600 accounts and tax computations. What it is, why it matters, and how to create it.
HMRC Free Filing Software Is Closing March 2026 — What Now?
HMRC is shutting down its free CT600 filing service on 31 March 2026. Here's what it means for your company and the cheapest alternatives.
Year-End Tax Planning: 7 Ways to Reduce Your Corporation Tax Before Filing
Legitimate strategies to reduce your Corporation Tax bill before your year-end. Pension contributions, capital allowances, salary timing, and more.
Sole Trader vs Limited Company Tax: Which Saves You More in 2025/26?
Complete tax comparison between sole trader and limited company structures. Income tax vs corporation tax, national insurance, dividends, and the crossover point.
10 CT600 Mistakes That Get Your Return Rejected by HMRC
The most common CT600 filing mistakes that cause HMRC rejections. Learn what to avoid so your Corporation Tax return gets accepted first time.
Sole Trader vs Limited Company: Tax Comparison 2025/26
Detailed tax comparison between operating as a sole trader vs limited company in 2025/26. Income Tax vs Corporation Tax, National Insurance, dividends, and when to incorporate.