CT600 Deadline: When Is Your Company Tax Return Due?
When is your CT600 due? Your company tax return deadline is 12 months after the accounting period ends. Late filing means automatic penalties.
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Plain-English guides to UK Corporation Tax and CT600 filing.
Corporation Tax Rates 2025/26 - Marginal Relief Calculator
UK corporation tax rates for 2025/26: 19% small profits rate, 25% main rate, and how marginal relief works for profits between £50,000 and £250,000.
What Records Do I Need for My Company Tax Return?
Complete checklist of records and documents needed for CT600 filing. How long to keep them, what HMRC expects, and how to organize everything.
CT600 Penalties: What Happens If You File Late?
Complete guide to CT600 late filing penalties and charges. How much you'll pay, when penalties apply, and how to appeal HMRC penalty decisions.
Do I Need an Accountant to File My CT600?
Honest assessment of when you need an accountant for CT600 filing vs when you can do it yourself. Costs, complexity, and decision factors explained.
Small Company Accounts: FRS 105 vs FRS 102 Explained
Which accounting standard should your small company use? Plain English comparison of FRS 105 micro-entity accounts vs FRS 102 small company accounts.
HMRC Free Filing Ended March 2026 — What You Need to Know
HMRC shut down its free CT600 filing service on 31 March 2026. Here's what changed, why it matters, and what your options are going forward.
What Is a CT600? The Plain English Guide for Company Directors
A jargon-free explanation of the CT600 Corporation Tax return — what it is, who needs to file one, what goes in it, and how to submit it to HMRC.