Guides
Clear, friendly help for filing your own company tax return.
How to file a dormant company tax return
If your company did not trade this year, here is exactly what you still need to send to HMRC and Companies House — and how to do it yourself in minutes.
Read guide →Micro-entity accounts, explained simply
Most of the UK’s smallest companies can file simplified “micro-entity” accounts. Here is how to know whether that includes you — and how to file them yourself.
Read guide →Filing your Corporation Tax return without an accountant
HMRC withdrew its free filing service on 31 March 2026. Here is how to file your company tax return yourself — and what goes into it.
Read guide →What is iXBRL (and why you don’t need to worry about it)
iXBRL is the digital format HMRC and Companies House require. Here is what it means — and why good software means you never have to touch it.
Read guide →Corporation Tax deadlines and penalties
The dates that matter for your company tax return, accounts and tax payment — and what it costs if you miss them.
Read guide →What you need before you file (UTR, Government Gateway and more)
A short checklist of everything to have to hand before you start your company tax return — and where to find each item.
Read guide →Corporation Tax rates and marginal relief, explained
How much Corporation Tax your company pays, why there is more than one rate, and what marginal relief means for smaller profits.
Read guide →Importing your figures from QuickBooks or Xero
If you keep your books in QuickBooks Online or Xero, you can bring your year-end figures straight into your return instead of entering them manually.
Read guide →The small company tax calendar: every date that matters
All the filing and payment dates a small UK limited company needs to track — HMRC, Companies House and the confirmation statement — in one place.
Read guide →Common mistakes when filing your first CT600
The errors first-time filers actually make — from mixed-up UTRs to long first accounting periods — and how to avoid each one.
Read guide →How to register for Corporation Tax
Just incorporated? Here is how Corporation Tax registration works, when to tell HMRC your company is active, and where your UTR comes from.
Read guide →Allowable expenses for a small limited company
Which costs reduce your company’s Corporation Tax bill, which do not, and the rules that catch people out — in clear terms.
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