HMRC Free CT600 Filing Is Ending March 2026
If you've been filing your Corporation Tax return for free through HMRC's online service, that's about to change. On 31 March 2026, HMRC will shut down its free CT600 filing tool.
What's Happening?
HMRC announced that their online Corporation Tax filing service will close on 31 March 2026. After that date, you'll need to use commercial software to file your CT600.
This affects every UK limited company that currently files directly through HMRC — estimated at 200,000 to 400,000 companies.
Why Is HMRC Doing This?
HMRC has been moving all tax services to the Making Tax Digital (MTD) platform. The old Corporation Tax service runs on legacy infrastructure that's expensive to maintain. Rather than rebuild it, HMRC is directing companies to use third-party software.
What Do You Need to Do?
If Your Year-End Is Before 31 March 2026
You can still file through HMRC's free service — but don't leave it to the last minute. The service may become unreliable as the shutdown date approaches.
If Your Year-End Is After 31 March 2026
You'll need commercial software. Your options:
- Taxpipe — £59 per filing, no subscription. Purpose-built for CT600. Guided wizard, automatic calculations, HMRC-validated.
- Accountant — £200-800+ per year. Overkill if your affairs are simple.
- Full accounting software — Xero, FreeAgent, Sage. £15-40/month (£180-480/year). More than you need if you only want to file CT600.
What Does CT600 Software Need to Do?
At minimum, commercial CT600 software must:
- Generate valid CT600 XML in HMRC's required format
- Produce iXBRL accounts and tax computations
- Submit directly to HMRC via their Government Gateway
- Handle HMRC's polling/acknowledgement workflow
This isn't something you can do in a spreadsheet. The XML and iXBRL requirements are strict.
The Cheapest Option
Taxpipe costs £59 per filing — that's it. No monthly subscription, no annual fee, no per-user charges. You pay once when you're ready to file.
For comparison:
- HMRC free service: £0 (closing March 2026)
- Taxpipe: £59/filing
- TinyTax: £60/filing
- FreeAgent: £19/month (£228/year)
- Xero: £15/month (£180/year)
- Accountant: £300-800/year
Don't Wait
The March 2026 deadline will sneak up fast. Set up your Taxpipe account now so you're ready when you need to file.
Taxpipe — CT600 filing made simple. £59, no subscription.