How DormantFile works
From sign-up to submitted in minutes. Set up once, we watch your deadlines, and when the time comes both returns go straight to Companies House and HMRC. No accounting knowledge needed.
Start here: which sounds like your company?
DormantFile is built for companies that aren't actively trading. Find the one that matches yours, and you'll know exactly what you need to file.
It's completely dormant
No transactions at all since it was set up, or since it stopped trading. You file dormant accounts to Companies House, plus a nil CT600 to HMRC if it's registered for Corporation Tax. This is the main path.
It's not trading, but has a transaction or two
Often a Bounce Back Loan being repaid. That stops it counting as dormant in law, so at the filing step you choose micro-entity (FRS 105) accounts instead, and we prepare them from a few figures. Read the micro-entity guide→
It's behind on its filings
We show every outstanding period for your company. File them one at a time, oldest first, and it's brought back up to date.
It's not registered for Corporation Tax
Then you only need annual accounts. Accounts and the CT600 are independent filings, so you can file one without the other. Read the Corporation Tax guide→
Get set up
about 2 minutesCreate an account, add your company, and pick a plan. That's the whole setup.
- 1
Check your company
Enter your company number on the start page. We pull its name, incorporation date and filing history from Companies House and show your deadlines — before you sign up.
- 2
Choose: watch free, or file
Watch your deadlines for free, or go on to file. You create your account here — just an email and a password.
- 3
File when you're ready
Preparing your return is free. A subscription unlocks filing: £19 a year for one company, £39 for up to 10, or £49 for up to 100, renewing annually until you cancel.
We watch your deadlines
automaticWe track your accounts deadline automatically — nine months after your accounting reference date (your first accounts get 21 months from incorporation). Then we email you in good time, so it never sneaks up.
Reminders sent at
Filing deadline in 30 days
from DormantFile
Your annual accounts for ACME HOLDINGS LTD are due on 28 April 2026.
Log in to your dashboard to file now →
CT600 return due in 7 days
File and confirm
about 2 minutesConfirm your details and submit. Both filings go directly to the government via official APIs.
File your accounts to Companies House
Submit your dormant or micro-entity accounts. Enter your authentication code and we generate the iXBRL document and submit it via the Companies House software filing API.
File your nil CT600 to HMRC
Enter your Government Gateway credentials. They're used once at submission and immediately discarded. We file directly via HMRC's GovTalk API.
Get your confirmation
Once a filing is accepted, we show confirmation in your dashboard and send you an email. Filing records are stored so you always have a history.
Then turn on autopilot for next year (optional)
Turn on autopilot any time from the company's autopilot page or settings. We save your authentication code encrypted (AES-256-GCM), prepare next year's dormant accounts, and email you 30 days before the deadline — one click files them. Rinse and repeat each year. Turning autopilot off keeps the code saved so re-enabling is one click; you can remove it from the company's settings at any time, which deletes it immediately. Dormant accounts only — your CT600 is always filed by you.
A closer look at the CT600
Corporation TaxYour Corporation Tax return is the one part you set up yourself, because only you know the periods HMRC has asked for. Here's how the Corporation Tax section works once you're inside DormantFile.
Turn on Corporation Tax
Enter your company's 10-digit UTR in settings to switch on the Corporation Tax section. No UTR, nothing to do — accounts and the CT600 are independent, so you only deal with this if HMRC asks for a return.
Add the period to file
You tell us the period HMRC expects a return for. We suggest the dates from your accounts and Companies House record, and you confirm them. A period longer than 12 months is split into two returns, as HMRC requires.
Attach your accounts
Every CT600 includes a copy of your statutory accounts. We staple on the ones you filed here, or you can fetch them from Companies House or upload your own iXBRL file.
Sign and submit the nil return
Confirm the director filing, preview the exact return, then enter your Government Gateway login to authorise it. We build the nil return — every figure zero — submit it to HMRC, and email you the moment it's accepted.
Already filed a period elsewhere? Mark it as filed to clear it from your list. For a full walkthrough, see how CT600 filing works in DormantFile.
See it in action
A walkthrough of the actual DormantFile dashboard.
EXAMPLE HOLDINGS LTD
Company number: 12345678
10 Example Street, London, EC1A 1BB
ActiveYour credentials stay yours
We never store your HMRC login details, and your Companies House code is only saved if you choose to save it. Here is exactly what happens to them.
Government Gateway
Used once at submission, then immediately discarded. Never stored, never logged.
Authentication code
Used in-session to sign your Companies House submission. Stored only if you choose to save it — encrypted (AES-256-GCM), never logged. Turning autopilot off keeps it saved so re-enabling is one click; remove it any time from the company's settings, which deletes it immediately.
Ready to get started?
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.