Best CT600 Filing Software UK 2026 — Compared
HMRC's free filing tool closes March 2026. Compare the best CT600 filing software options — prices, features, and which one suits your company.
Plain-English guides to UK Corporation Tax and CT600 filing.
HMRC's free filing tool closes March 2026. Compare the best CT600 filing software options — prices, features, and which one suits your company.
How to claim AIA on your CT600 for plant and machinery purchases. What qualifies, what doesn't, and common mistakes that cost small companies money.
How to optimise your salary and dividends mix as a limited company director. Save thousands in tax with the right strategy — and how it affects your CT600.
Missed your CT600 deadline? Learn about HMRC penalties (£100 to 10% surcharges), interest charges, how to appeal, and the fastest way to get back on track.
How IR35 affects your Corporation Tax return. Inside vs outside IR35, deemed payments, and guidance for contractor companies.
R&D tax credits for SMEs: what qualifies, how to calculate the relief, and which CT600 boxes to complete. Plain English guide.
How to use trading losses on your CT600 return. Carry forward, carry back, group relief, and which CT600 boxes to complete for loss relief claims.
Filed your CT600 and spotted an error? Here's how to amend your Corporation Tax return, the time limits, and what happens if HMRC finds the mistake first.
Just set up a limited company? Everything you need to know about your first CT600 — when it is due, what to include, and how to file.
How to claim capital allowances on your CT600. AIA, full expensing, car rules, and writing down allowances for small companies.
The most frequent errors company directors make when filing their CT600. From wrong dates to missing boxes — and how to get it right first time.
Your dormant company still needs to file a CT600 with HMRC. Learn what counts as dormant, how to file, and the fastest way to stay compliant for just £59.