Annual accounts to Companies House and nil CT600 returns to HMRC — filed directly via official APIs. No accounting knowledge needed.
For genuinely dormant companies only — no trading activity, no assets, no income.
Your options for filing a dormant company's returns.
Your accountant
Accounting software
DormantFile
From company number to filed returns — here's the whole process.
Type your company number. We pull your name, incorporation date, and filing history from Companies House automatically.
Email reminders at 90, 30, 14, 7, 3, and 1 day before each filing is due. We calculate the dates — you just show up.
Confirm your details and submit. Dormant accounts go to Companies House and your nil CT600 goes to HMRC — both via official APIs.
Here's what's working behind the scenes.
We check Companies House for every unfiled period since your company was incorporated. Nothing slips through.
Reminders at 90, 30, 14, 7, 3, and 1 day before each filing is due — with penalty amounts so you know the stakes.
Your company data is synced against Companies House daily. Periods filed elsewhere are detected and marked automatically.
A complete filing walkthrough in under two minutes.
31 March 2026
HMRC shut down CATO — the only free way to file a Corporation Tax return. If you're a director of a dormant company, you still need to file every year or face penalties.
What you still need to file
Annual accounts
To Companies House — every year, for every company
Nil CT600 return
To HMRC — every year, if registered for Corporation Tax
DormantFile handles both. From £19/yr.
Start filingEvery plan includes annual accounts and CT600. No add-ons, no hidden fees.
Basic
You have one dormant company on the register.
Multiple
£3.90 per company
Side projects, holding structures, or a few companies on the register.
Agent
49p per company
For accountants and formation agents filing on behalf of clients.
Compare to £100+ for most accounting software. All plans include credentials-never-stored security.
Built by Ben
Founder & developer
DormantFile exists because the old tools either shut down or were never built for this job. I'm a UK software engineer, and I built it from scratch — not adapted from accounting software, not a side feature in a bigger product.
Your filings go through the same official HMRC GovTalk and Companies House Software Filing APIs that Xero and FreeAgent use. Same infrastructure, fraction of the price, and nothing you don't need.
The details that matter
Official APIs
Filed via HMRC GovTalk and CH Software Filing — the same APIs the big tools use.
Credentials never stored
Your HMRC Gateway password is used once at submission, then immediately discarded from memory.
Your data, transparent
We store your company info, email, and filing history. We never store passwords, financial data, or card details.
14-day refund guarantee
Full refund within 14 days if you haven’t filed. No questions, no hoops.
Founder-direct support
Email support with replies within one working day. You talk to the person who built it.
The things we'd want to know before signing up. See all FAQs →
No. DormantFile is for genuinely dormant companies only — no income, no expenditure, no assets. If your company has been trading, you’ll need a full accountant.
Yes, to file the CT600 you’ll enter your Government Gateway credentials. They’re used once at submission and immediately discarded — never stored.
Yes. You can file any outstanding period, not just the current one. Catch up on missed years in a single sitting.
You’ll see the rejection reason in your dashboard and can correct and resubmit. Common causes are simple data mismatches that take seconds to fix.
That’s fine. Most dormant companies only need annual accounts. You can skip CT600 filing if your company isn’t registered for Corporation Tax.
Yes — the Agent plan covers up to 100 companies and supports filing on behalf of clients. It’s £49 a year, which works out to 49p per company.
Plain-English guides, answers, and free tools for dormant company directors.
Or jump straight to a topic hub: CT600 for dormant companies · Companies House for dormant companies
From
£19/yr
Under
2 min
Filings
2
Set up your company in minutes. When it's time to file, both returns go directly to Companies House and HMRC. From £19 a year.