Free CT600 Options After HMRC Closes in 2026
HMRC's free Company Accounts and Tax Online (CATO) service closes on 31 March 2026. But that doesn't mean you have to start paying to file your CT600. Genuinely free alternatives exist.
The Good News
You can still file CT600 returns for free after March 2026. Commercial software doesn't automatically mean expensive software. Free options exist that match or exceed HMRC's old service.
Free CT600 Software Options
TinyTax — Genuinely Free
Cost: £0 for micro-entity companies
TinyTax is purpose-built as a free replacement for HMRC's service. No tricks, no trials, no hidden fees.
What's included free:
- Full CT600 return preparation
- Electronic submission to HMRC
- iXBRL accounts generation
- Companies House accounts filing
- Trial balance import (from Xero, QuickBooks, etc.)
- Corporation tax calculation
- Error checking and validation
- Unlimited filings
- No subscription
- No credit card
- No "upgrade to file"
- No per-filing charges
Start filing free with TinyTax →
Government Gateway — Limited Functionality
Cost: Free (but not for filing CT600)
After March 2026, Government Gateway remains available but you cannot file CT600 returns through it. You can only:
- Pay Corporation Tax
- View your tax account
- Manage other HMRC services
HMRC Basic Tools — Not Available
There is no "basic" HMRC filing option after March 2026. The government has decided to exit the CT600 filing software market entirely.
Paid Options (For Comparison)
If you need features beyond micro-entity filing, paid options include:
| Software | Starting Price | Key Features |
|---|---|---|
| TaxCalc | £100+/year | Multi-company, accountant tools |
| IRIS | £200+/year | Practice management |
| Sage | £150+/year | Sage accounting integration |
| BTCSoftware | £100+/year | Professional filing |
What Makes TinyTax Different?
1. Built for Small Companies
TinyTax was designed specifically for director-managed small companies — not as a "lite" version of accountant software.
2. No Subscription Model
Many "free" software options require upgrading to actually submit your return. TinyTax submission is completely free.
3. Dual Filing
File to both HMRC (CT600) and Companies House (accounts) from one platform. No need for separate software.
4. Modern Interface
Clean, guided workflow that's easier than HMRC's ageing CATO system.
5. Trial Balance Import
Import from popular accounting software instead of manually entering figures.
Common Questions About Free Filing
Is there really free CT600 software?
Yes. TinyTax offers genuinely free CT600 filing for micro-entity companies. There's no catch — it's funded through premium features for accountants and larger companies.
What's the difference between free and paid software?
| Feature | TinyTax (Free) | Paid Software |
|---|---|---|
| Single company filing | ✓ | ✓ |
| CT600 submission | ✓ | ✓ |
| iXBRL accounts | ✓ | ✓ |
| Companies House filing | ✓ | ✓ |
| Multi-company support | Limited | ✓ |
| Practice management | ✗ | ✓ |
| Advanced tax planning | ✗ | ✓ |
Will free software be as good as HMRC's service?
Actually better. TinyTax offers:
- Real-time validation (HMRC's system often showed errors only after submission)
- Trial balance import (HMRC required manual entry)
- Combined CH/HMRC filing in one workflow
- Modern, mobile-friendly interface
What if I'm not a micro-entity?
TinyTax works for small companies too. For larger or more complex companies, you may need features from paid software like TaxCalc or IRIS.
Do I qualify as a micro-entity?
To be a micro-entity, your company must meet at least two of these criteria:
- Turnover not more than £632,000
- Balance sheet total not more than £316,000
- Average employees not more than 10
Can I switch from free to paid software later?
Yes. If your company grows or needs change, you can switch software anytime. Your HMRC/Companies House accounts remain unchanged.
How to Get Started with Free Filing
Step 1: Create Your Account
Visit tinytax.co.uk/register and sign up with your email.Step 2: Add Your Company
Enter your company registration number. TinyTax automatically imports company details from Companies House.Step 3: Connect to HMRC
Authorise TinyTax through Government Gateway (takes 2 minutes).Step 4: Import or Enter Figures
Upload a trial balance from your accounting software, or enter figures manually.Step 5: Review and Submit
TinyTax calculates your tax, generates iXBRL accounts, and submits electronically.Timeline: When to Switch
| Deadline | Action |
|---|---|
| Now | Create TinyTax account |
| Before March 2026 | File at least one return through TinyTax |
| 31 March 2026 | HMRC service closes |
| From April 2026 | All CT600 filings through software |
- Learn the software without time pressure
- Resolve any issues before HMRC closes
- Compare the experience while both options exist
Frequently Asked Questions
Why is TinyTax free?
TinyTax is free for individual company filings to help small businesses transition from HMRC's service. Revenue comes from accountants and larger organisations using premium features.
Is my data safe?
Yes. TinyTax uses bank-grade encryption and secure connections. Your financial data is protected.
What if I need help?
TinyTax includes built-in guidance for each CT600 box. Support is available if you get stuck.
Can I file amendments for free?
Yes. Amendments to previous returns can be filed through TinyTax at no cost.
What about dormant companies?
Dormant companies can file for free through TinyTax. The simplified accounts format is fully supported.
Summary
- Free CT600 filing exists after HMRC closes
- TinyTax offers genuinely free filing for micro-entities
- No subscription, no hidden fees, no upgrade requirements
- Switch now to prepare before the March 2026 deadline
File your CT600 for free. Create your TinyTax account →