Free CT600 Filing Software: What Are Your Options in 2026?
If you're looking for free CT600 filing software in 2026, there's some bad news: the only genuinely free option is gone. HMRC's own free filing service closed on 31 March 2026, and most alternatives cost hundreds of pounds per year.
Here's what's actually available — and what it really costs.
HMRC's Free Filing Service (Closed 31 March 2026)
Until 31 March 2026, HMRC and Companies House ran a joint free online service for filing Company Tax Returns and annual accounts. For years it was the go-to option for small companies filing themselves.
What it offered:
- CT600 form completion and basic tax calculation
- iXBRL accounts and tax computations generated automatically from the figures you keyed in — no separate iXBRL software needed
- Direct submission to HMRC
- Optional joint filing of accounts to Companies House in the same session
- Free (taxpayer funded)
What it didn't offer:
- Support for anything beyond simple, unrepresented small companies — companies with more complex affairs were outside its eligibility rules
- Supplementary pages for specialist scenarios
- Much guidance beyond the form itself — you still needed to understand your own figures
- Error checking beyond basic validation
The catch: HMRC shut this service down on 31 March 2026. Since then, every company has needed third-party commercial software (or an accountant) to file a CT600.
After March 2026: Your Options
Option 1: Accountant Software (Not Free)
Professional accounting software like Xero, FreeAgent, or Sage can file CT600 returns. But they're designed for accountants, not company directors.
| Software | Cost | CT600 Filing? | Notes |
|---|---|---|---|
| Xero | From £15/month (£180/year) | Via add-on only | Need accountant to file |
| FreeAgent | From £19/month (£228/year) | Yes (with limitations) | Best for freelancers |
| Sage | From £12/month (£144/year) | Via accountant | Complex setup |
| QuickBooks | From £12/month (£144/year) | No CT600 filing | Bookkeeping only |
The problem: These are subscription services. You're paying £150-£230 per year even though you only file once a year. And most still require an accountant to actually submit the CT600.
Option 2: Specialist CT600 Software
Dedicated CT600 filing tools are built specifically for company tax returns.
| Software | Cost | iXBRL Included? | Target User |
|---|---|---|---|
| EasyDigitalFiling | From £125/filing | Yes | DIY directors |
| TaxCalc | From £199/year | Yes | Accountants |
| Andica | From £99/year | Yes | Small practices |
| Taxpipe | £59/filing | Yes* | DIY directors |
*Taxpipe generates iXBRL accounts for micro-entity (FRS 105) and dormant companies. If you file under FRS 102 Section 1A (small company), you must supply your own iXBRL accounts — Taxpipe handles submission only.
Option 3: Hire an Accountant
Average cost for a small company CT600 filing: £300-£800 per year. This includes:
- Preparing annual accounts
- Filing with Companies House
- Completing and filing the CT600
- Tax planning advice
Worth it if: Your affairs are complex (property, multiple income streams, R&D claims, employees).
Overkill if: You're a simple one-person company with straightforward trading income.
Option 4: DIY with Spreadsheets (Not Recommended)
Technically, you could calculate everything in a spreadsheet and use any HMRC-recognised software just for submission. But:
- You still need to generate iXBRL accounts
- You need to know every CT600 box to fill in
- No validation = high risk of errors
- Errors mean penalties and interest
What "Free" Really Costs
The cheapest approach isn't always the best value. Consider the total cost:
| Approach | Direct Cost | Time | Risk of Errors | Total Real Cost |
|---|---|---|---|---|
| HMRC free tool (closed March 2026) | £0 | 4-8 hours | Medium-High | No longer available |
| Accounting software subscription | £150-£230/year | 2-4 hours | Medium | £150+ ongoing |
| Specialist CT600 software | £59-£199/filing | 1-2 hours | Low | One-off per filing |
| Accountant | £300-£800/year | 0 hours | Very Low | Professional fee |
| DIY spreadsheet + basic software | £0-£50 | 8-16 hours | High | Your time + risk |
Why Most "Free" Options Aren't Really Free
Hidden Costs of Cheap Tools
- Your time: If it takes 8 hours and your time is worth £30/hour, that's £240
- Error risk: A mistake that triggers an HMRC enquiry costs £500+ in accountant fees to resolve
- Missing iXBRL: HMRC requires iXBRL accounts. Generating these separately can cost £50-£100
- No support: If something goes wrong, you're on your own
The Subscription Trap
Monthly accounting software costs £144-£228 per year, but you only file once. You're paying 11 months of subscription for a once-a-year task.
The Taxpipe Approach
Taxpipe takes a different approach:
- £59 per filing — not per month, not per year
- Everything included: CT600, iXBRL micro-entity accounts (FRS 105 / dormant), tax computations, HMRC submission — FRS 102 Section 1A filers upload their own iXBRL
- Guided process: Answer questions in plain English, we fill in the correct boxes
- Automatic calculations: Financial-year rate splitting, marginal relief, capital allowances
- No subscription: Pay once when you file, nothing in between
Who Taxpipe Is Built For
- One-person limited companies
- Freelancers and contractors trading through a company
- Small businesses with straightforward affairs
- Directors who previously used HMRC's free tool
- Anyone who doesn't want to pay an accountant £500 for a simple filing
Who Should Use an Accountant Instead
- Companies with complex tax affairs (multiple entities, international income)
- Companies claiming R&D tax credits for the first time
- Companies with property portfolios and multiple income streams
- Companies going through HMRC enquiries
Making the Switch from HMRC Free Filing
If you used HMRC's free tool, here's what changed after March 2026:
- Same obligation — you still need to file a CT600
- Same deadline — 12 months after your period end
- Different tool — you now need commercial software or an accountant
- Companies House is separate — the HMRC service let you file accounts to Companies House in the same session; commercial CT600 software handles the HMRC side, and you file your Companies House accounts separately
The silver lining: Good commercial software makes filing easier than HMRC's basic tool did. Less manual box-filling, more guidance, better error checking.
Switch to Taxpipe — £59, everything included →
Related Articles
- HMRC Free Filing Is Ending March 2026
- Best CT600 Filing Software UK 2026
- File CT600 Without an Accountant
- Do I Need an Accountant to File My CT600?
- CT600 Filing Checklist
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