HMRC Free CT600 Filing Has Closed: What Are Your Options?
HMRC's free Corporation Tax filing service closed permanently on 31 March 2026. If you were using it to file your CT600 returns, you now need a commercial alternative.
This guide explains what happened, why, and what your best options are going forward.
What Happened?
HMRC withdrew its free online service for filing CT600 Corporation Tax returns on 31 March 2026. From that date, you can no longer:
- File CT600 returns through HMRC's website
- Use HMRC's free filing tool
- Access the HMRC CT600 filing interface
This affects every UK limited company that previously used HMRC's free service to file their Corporation Tax returns.
Why Did HMRC Close the Free Service?
HMRC modernised its systems and moved towards a model where commercial software providers handle tax filing. This is the same approach used for:
- MTD for VAT — already requires commercial software
- MTD for Income Tax — launched April 2026 for the highest earners
- PAYE — already uses commercial software (Basic PAYE Tools or payroll software)
HMRC wants to focus on processing returns and compliance, not building filing software.
How Many Companies Are Affected?
An estimated 200,000–400,000 UK limited companies previously used HMRC's free filing service. These are typically:
- One-director companies with simple affairs
- Dormant companies that have received a notice to deliver from HMRC
- Directors who file their own CT600 without an accountant
- Companies that don't want to pay accountant fees for simple returns
If you're one of them, here are your options.
Your Options After March 2026
Option 1: Taxpipe — £59 per Filing (Recommended)
Taxpipe is designed specifically as a replacement for HMRC's free filing service:
- Guided wizard — walks you through every CT600 box in plain English
- Auto tax calculation — including marginal relief and financial year splits
- iXBRL accounts included — micro-entity accounts generated automatically
- Direct HMRC submission — files electronically via the Government Gateway
- One-time fee — £59 per return, no subscription
Why it's the closest alternative to HMRC's free service:
- Simple, self-service interface (no accountant needed)
- Designed for directors who file their own returns
- Much cheaper than hiring an accountant
Option 2: Accountant — £300–£800+ per Year
If you prefer someone else to handle your CT600:
- Find a local or online accountant
- They'll prepare and file your CT600 using professional software
- Costs vary widely depending on complexity
Best for: Companies with complex affairs (multiple trades, international income, R&D claims)
Option 3: Other CT600 Software
Several commercial software packages can file CT600 returns:
| Software | Price | Best For |
|---|---|---|
| Taxpipe | £59/filing | DIY directors, simple companies |
| TaxCalc | ~£70/filing | DIY directors |
| GoSimpleTax | ~£58/filing | DIY directors |
| Xero Tax | Needs accountant access | Accountants |
| Sage | From £420/year | Larger companies |
What You Should Do Now
- Act promptly — the free service has closed; any returns still to file need a commercial tool
- Choose your replacement software — sign up and familiarise yourself with it
- File outstanding CT600s — late-filing penalties apply from day one
- Set up for future filings — most directors find the process straightforward once they've done it once
Key Dates
| Date | What Happened / What To Do |
|---|---|
| 31 March 2026 | HMRC free filing service closed permanently |
| 1 April 2026 | All CT600 filing moved to commercial software |
| Now | File outstanding returns using commercial software |
Dormant Companies: When Do You Need to File?
If your company is dormant (not trading), whether you need to file a CT600 depends on whether HMRC has issued you a notice to deliver a return.
If you have told HMRC your company is dormant: HMRC will normally stop sending notices to deliver. Once you have informed HMRC of dormancy, you do not need to file a CT600 unless and until HMRC issues a notice. You can notify HMRC of dormancy using HMRC's online service.
If HMRC has issued a notice to deliver a return: You must file — even if the company is dormant. A dormant CT600 is the simplest possible return: most boxes are zero, there is no tax to pay, and Taxpipe's guided wizard detects dormant companies and fast-tracks the process.
The free service closure affects dormant companies that do need to file (i.e. those that have received a notice from HMRC). If you haven't told HMRC your company is dormant, do that first — it may remove the obligation to file entirely.
Frequently Asked Questions
Will HMRC bring the free service back?
Almost certainly not. HMRC has been gradually shifting to commercial software for years (VAT, PAYE, Income Tax). The CT600 free service was the last one to go, and there has been no suggestion of a reversal.
Can I still file CT600s after March 2026?
Yes — just not through HMRC's free tool. You'll use commercial software (like Taxpipe) that submits to HMRC electronically.
Do I need to change my Government Gateway login?
No. Your Government Gateway credentials stay the same. Commercial software uses the same HMRC system — it just submits your return through the API instead of HMRC's web interface.
Is £59 really the cheapest option?
For a professional, HMRC-compliant CT600 filing with iXBRL accounts, £59 is among the lowest prices available. Compare it to £300+ for an accountant or £70+ for other software.
What if I can't afford filing software?
If cost is a concern, remember that a CT600 is a legal obligation — the penalties for not filing are far more expensive. For returns with a filing deadline on or after 1 April 2026:
- 1 day late: £200 penalty
- 3 months late: another £200
- 6 months late: 10% of unpaid tax
- 12 months late: another 10% of unpaid tax
At £59, Taxpipe is far cheaper than any late-filing penalty.
The Bottom Line
The HMRC free filing service was convenient but basic. The transition to commercial software is an opportunity to switch to tools that are actually better:
- ✅ Guided wizard (HMRC's tool was confusing)
- ✅ Automatic tax calculations (HMRC made you calculate everything yourself)
- ✅ Error checking before submission (HMRC rejected returns without clear explanations)
- ✅ iXBRL accounts included (HMRC's tool didn't generate these)
The process is straightforward — sign up, enter your figures, and submit. Most directors complete their first Taxpipe filing in under 30 minutes.
The free service has closed. Sign up for Taxpipe today and file your CT600 the easy way.