CT600 Filing Agent Authorisation with HMRC
How to authorise an agent to file your CT600. Step-by-step guide to HMRC agent authorisation for corporation tax — online, by post, and what to do if things go wrong.
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Plain-English guides to UK Corporation Tax and CT600 filing.
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Corporation Tax Marginal Relief Explained
How does marginal relief work for UK corporation tax? Plain-English explanation of the 19%-25% band, the formula, worked examples, and how to claim on your CT600.
Optimal Director Salary 2025/26 Tax Year
Find the most tax-efficient director salary for 2025/26. We explain the NIC thresholds, employer costs, and how to save thousands through your limited company.
Corporation Tax Relief on Charity Donations
How to claim corporation tax relief on charitable donations. Covers qualifying payments, Gift Aid, non-cash gifts, and how to report donations on your CT600.
Employer NIC: Corporation Tax Deduction Guide
Is employer NIC an allowable deduction for corporation tax? Yes. Learn how employer National Insurance works, current rates, the Employment Allowance, and how to claim on your CT600.
Flat Rate VAT Scheme & Corporation Tax
How the Flat Rate VAT Scheme affects your corporation tax. Learn about the VAT surplus, how to report it on your CT600, and whether the scheme still saves money.
HMRC Corporation Tax Refund: How Long?
How long does an HMRC corporation tax refund take? Typical timescales, what causes delays, how to chase a late repayment, and tips to get your refund faster.
HMRC Penalties for Late Corporation Tax Filing
What are the penalties for filing your CT600 late? Understand HMRC penalty rates, interest charges, and how to avoid or appeal late filing penalties.
Pension Contributions & Corporation Tax Relief
How employer pension contributions reduce your CT600 corporation tax bill. Limits, timing rules, and how to claim the deduction for your limited company.
R&D Tax Credits for SMEs: Complete Guide to Claiming
How UK small and medium-sized companies can claim R&D tax credits. Covers eligibility, qualifying costs, calculation examples, the merged scheme, and how to include R&D relief on your CT600.
Overdrawn Director's Loan Account & S455 Tax Explained
Owe money to your company? Learn how an overdrawn director's loan account triggers S455 tax on your CT600, how much you'll pay, and how to get it back.
How to Appeal a CT600 Late Filing Penalty from HMRC
Got a CT600 late filing penalty? You may be able to appeal. Step-by-step guide to HMRC penalty appeals, reasonable excuses, and time limits.