Dormant Company Accounts & CT600: Filing Guide for Companies That Aren't Trading
A dormant company still has filing obligations. Here's what you need to do and when.
What Makes a Company Dormant?
A company is dormant if it has had no significant accounting transactions during the period. The only transactions allowed are:
- Payment for shares on incorporation
- Filing fees paid to Companies House
- Late filing penalties
If there's been any other financial activity — bank interest, a single invoice, a director's loan — the company is not dormant.
HMRC vs Companies House: Different Definitions
Companies House considers a company dormant if it's had no significant accounting transactions.
HMRC considers a company dormant for Corporation Tax if it's not active (not trading, no income). You can tell HMRC your company is dormant, and they'll stop sending CT600 notices.
But be careful: If you told HMRC you're dormant and then start trading again, you must tell them within 3 months or face penalties.
Filing Requirements
Companies House (Annual Accounts)
Dormant companies can file dormant accounts — a simplified balance sheet showing:
- Share capital
- Net assets (usually equal to share capital)
- No profit & loss account needed
Filing deadline: 9 months after your accounting reference date.
HMRC (CT600)
If HMRC knows you're dormant, they won't require a CT600. But if they don't know (or if they still send you a notice), you must file a nil CT600.
A nil CT600 shows:
- Zero turnover
- Zero profit
- Zero tax payable
- All boxes zero except company information
Confirmation Statement (Companies House)
Dormant or not, you must file a confirmation statement at least once every 12 months. Fee: £13 (online).
How to Tell HMRC You're Dormant
New companies: When you register for Corporation Tax, tell HMRC the company is dormant. They won't issue CT600 notices.
Existing companies: Write to your Corporation Tax office or call the CT helpline (0300 200 3410) to notify them.
Reactivating: If you start trading again, notify HMRC within 3 months of the first transaction.
Filing a Nil CT600 with Taxpipe
Taxpipe makes filing a dormant company CT600 simple:
- Enter your company details
- The wizard detects dormant status
- All boxes auto-fill with zeros
- Review and submit — takes less than 5 minutes
Common Mistakes
- Not filing at all — penalties still apply to dormant companies that haven't told HMRC
- Forgetting bank interest — even £1 of interest means you're not dormant for HMRC
- Missing the confirmation statement — Companies House will start strike-off proceedings
- Not telling HMRC when you restart — 3-month notification deadline
Cost of Keeping a Dormant Company
| Item | Annual Cost |
|---|---|
| Confirmation statement | £13 |
| Dormant accounts (filed online) | £0 |
| CT600 filing (if required) | £59 via Taxpipe |
| Registered office (if needed) | £50-£200 |
Related: HMRC penalties for late filing
Related: closing your company and final CT600
Related: confirmation statement guide
Need to file a nil CT600 for a dormant company? Use Taxpipe — £59, auto-fills zeros, done in 5 minutes.