How to File CT600 Online in 2026: Complete Step-by-Step Guide
HMRC's free filing service closes 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.
Plain-English guides to UK Corporation Tax and CT600 filing.
HMRC's free filing service closes 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.
Not sure which CT600 supplementary pages to file? This guide explains each page — CT600A to CT600J — and tells you exactly which ones your company needs.
Full expensing lets your company deduct 100% of qualifying plant and machinery costs immediately. Here's who qualifies, what's included, and how to claim on your CT600.
HMRC's free Corporation Tax Online service closes 31 March 2026. Here's what happens next and the cheapest ways to file your CT600 after the deadline.
Corporation tax rates for 2025/26: 19% small profits rate, 25% main rate, and marginal relief in between. Includes worked examples and thresholds.
Box 155 is the most important number on your CT600. Learn exactly what trading profits means, how to calculate it, and common mistakes to avoid.
HMRC requires iXBRL for CT600 accounts and tax computations. What is it, why does it matter, and how do you create it? Plain English guide for directors.
Overpaid corporation tax? Learn how to claim a refund from HMRC, how long it takes, and what to do if your refund is delayed.
How much salary and dividends should you take? We calculate the optimal split for UK limited company directors in 2025/26, including the impact on corporation tax.
Filed your CT600? Here's what happens next — HMRC processing times, status updates, potential enquiries, and when to expect confirmation.
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.
Step-by-step guide to paying your corporation tax bill. Covers all payment methods, deadlines, payment references, and what happens if you pay late.