What 'dormant' actually means
A company is dormant for a financial period if it has had no significant accounting transactions — the entries that would otherwise appear in its accounting records. A holding company with no trade, a company incorporated to protect a name, a business waiting to start: all commonly dormant.
The subtlety that catches people is that dormancy has two separate tests. Companies House has one; HMRC has another. A company can be dormant for accounts but not for Corporation Tax, or the reverse. You have to satisfy both — not assume that clearing one clears the other.
The two filings you actually make
Being dormant reduces what you file. It doesn't remove it. There are two things to deliver, to two different registers:
- Dormant accounts to Companies House. A company that has never traded and is limited by shares can use the very short AA02 form; others file dormant accounts prepared under the micro-entity rules (FRS 105). Either way the numbers are minimal — but the filing is not optional.
- A nil CT600 to HMRC — but only if HMRC has asked for one. If HMRC has issued a notice to deliver a Company Tax Return, you must respond, and for a dormant company that's usually a return showing no tax due.
The Corporation Tax trap
Here is the mistake that costs money. Filing your dormant accounts at Companies House does not deal with HMRC. They are different bodies, different systems, different acknowledgements. A director files the accounts, sees "submitted", and believes the year is done — while a notice to deliver a CT600 sits unanswered.
The £100 half-done year
The clean path is to tell HMRC the company is dormant early — before a notice is issued — so no CT600 is required at all. If a notice has already been issued, file the nil return or ask HMRC to withdraw the notice.
Deadlines and penalties
- First accounts
- 21 months after the date of incorporation for a first set of accounts.
- Later accounts
- 9 months after your accounting reference date every year after that.
- Late-accounts penalty
- £150 → £375 → £750 → £1,500 as you go later, and doubled if last year's were late too.
The penalties are automatic and Companies House does not accept "I thought we were dormant, so it didn't matter" as a reason. Dormant companies get penalised on exactly the same ladder as trading ones.
How WrenTax does it
WrenTax prepares the dormant accounts and the nil CT600 together, shows you the exact documents before anything is submitted, files to both registers, and tracks each acknowledgement separately — so the deadline only clears when the register in question actually says yes. You can also watch any company's deadlines for free, no account needed. This guide is general information, not tax advice.