A company that was set up but has never started trading usually owes no Corporation Tax. HMRC may still send it a notice to deliver a Company Tax Return, and once it has, the company must file a return. For a company with no income and no expenses that return is a nil CT600: every figure is blank or zero and the tax due is £0.00. This article walks through filing one in Tax Optimiser, using a company that was incorporated on 1 April 2025, issued one £1 share and has done nothing since.
Do you need to file a return?
For Corporation Tax, a company is dormant while it is not carrying on a business and has no income — no sales, no bank interest, no rent. A company that has never traded is usually dormant from the day it was incorporated.
- HMRC has sent a notice to deliver a Company Tax Return (letter CT603, or a reminder in your HMRC online account): you must file a return for the period in the notice, even though there is nothing to pay. This article shows how.
- No notice has arrived: you don’t need to file a CT600. You can tell HMRC the company is dormant so it doesn’t expect returns (see HMRC’s dormant for Corporation Tax guidance).
Separately, every company must file accounts with Companies House each year, including one that has never traded. Those are the dormant accounts you prepare below, and the same accounts are attached to the CT600. Filing them at Companies House is covered in Filing dormant company accounts.
Heads up — if the company received any income, even a few pounds of bank interest, it is not dormant for Corporation Tax and the return is not nil: the interest is taxable. Enter it in the trial balance and follow the normal Corporation Tax guide instead.
Set up the company and the period
Sign up and create an accounting period as for any company (see Getting started with Corporation Tax). Two points matter for a nil return:
- Period dates. Use the dates of the company’s financial year — for a first period, from the date of incorporation to the accounting reference date. If HMRC’s notice gives a different period, keep the accounts dates on the period and use CT Dates → Override on the period Overview to file the return for the notice’s dates.
- No prior year. A first period has nothing to compare against, so on the period Overview choose Exclude next to Comparative. The accounts and the CT600 then show a single year.
Add the company’s Corporation Tax UTR (the ten-digit reference on HMRC’s letters) and at least one director, as usual.
Mark the period as dormant and never traded
Open View Accounts and, under Actions, click Company Information. Tick Dormant company and Company has never traded, and untick Draft accounts once you are ready to file. A short Principal Activities Description such as “The company has not traded since incorporation” is useful too. Click Save changes.
This switches the accounts to the dormant format and tags them as never traded, and the period is charged at the lower dormant submission fee.
Enter the trial balance
A company that has never traded has no profit and loss account at all. Its balance sheet usually holds just the share capital. In the example, one £1 share was issued and hasn’t been paid for yet, so the trial balance has two lines:
| Account | Debit | Credit |
|---|---|---|
| Share capital not paid | 1.00 | |
| Shares issued | 1.00 |
If the subscriber did pay for the share, debit the bank account instead of Share capital not paid. Open Trial Balance, enter the figures and click Save All. Hide Zero then shows only the lines you used.
Check the accounts under View Accounts → Statement of financial position. A dormant balance sheet carries the section 480 statement that the company was dormant and is exempt from audit. You don’t need to type it; it appears because you ticked Dormant company.
Check the computation: everything is nil
Open Corp Tax Calculations. The Corp Tax Payable headline reads £0.00. The P & L section says No profit and loss items found. For a company that has never traded that is exactly right, so there is nothing to fix.
The other sections (capital allowances, losses, loans to participators and so on) stay empty. Leave the questions in General at their defaults unless one genuinely applies. The CT600 Boxes section shows what will be filed. Turnover (box 145), trading profits (box 155), profits chargeable (box 315), Corporation Tax (box 430) and tax chargeable (box 510) are all nil.
The CT600 PDF (CT600 Document under Output Documents) shows the same. Box 80 is ticked because the dormant accounts and the computation are attached, and the tax calculation boxes are blank.
For what each box means, see the CT600 box guide.
Pay the dormant submission fee
The first time you open Corp Tax Submission for the period, you are asked to pay the per-period submission fee. Because the period is marked dormant it is charged at the Dormant rate. One payment covers both the CT600 and the Companies House filing for the period.
Submit the return to HMRC
The Corporation Tax Submission wizard is the same one every company uses (it is covered step by step in Submitting your Corporation Tax return). On the first step:
- HMRC Government Gateway credentials: the company’s (or your agent’s) Corporation Tax online login.
- Corporation Tax UTR: from HMRC’s notice.
- Director Signage Date: the date the director approved the accounts.
- Company Type: leave as Not applicable for an ordinary limited company.
- Director Accepting the Declaration: the director signing the return.
A warning about the employee count is normal for a dormant company. An average of 0 employees is correct, and the warning doesn’t stop you going on.
Click Next through Verification (confirm the client has approved the return), Review Document (the dormant accounts) and Review Calculation (the computation and the CT600 PDF). On Send Tax Return, check the summary and click Submit. The accounts and computation go to HMRC in iXBRL with the CT600, and the submission status updates when HMRC replies.
After you file
- Deadline. The return is due 12 months after the end of the period it covers. HMRC’s late-filing penalties apply even when there is no tax to pay, so file on time.
- Companies House. File the same dormant accounts at Companies House if you haven’t already — see Filing dormant company accounts.
- When the company starts trading. Tell HMRC within three months of starting to trade. From then on, create the next period as normal, untick Dormant company and Company has never traded, and enter the year’s figures.
Frequently asked questions
My company has never traded. Do I have to file a CT600?
Only if HMRC has sent a notice to deliver a Company Tax Return. If it has, you must file a return for the period in the notice, even if everything on it is nil. If it hasn’t, you can tell HMRC the company is dormant instead.
Do I still attach accounts to a nil return?
Yes. The CT600 goes with the company’s accounts and a tax computation, both in iXBRL. Tax Optimiser attaches the dormant accounts and a nil computation for you and ticks box 80.
Is dormant for HMRC the same as dormant for Companies House?
Not quite. Companies House looks at whether the company had any significant accounting transactions. HMRC looks at whether it carried on a business or received income. A company that has never traded and has no income is usually dormant for both.
The company earned a little bank interest. Is the return still nil?
No. Interest is taxable income, so the company isn’t dormant for Corporation Tax. Enter the interest in the trial balance; it is taxed as a non-trading loan relationship credit.
Is there a penalty for filing a nil return late?
Yes. HMRC’s late-filing penalties are fixed amounts that apply whether or not any tax is due.
Why does the P & L section say no profit and loss items were found?
Because there aren’t any. A company that has never traded has no income or expenses, so the message is expected and the computation correctly shows £0.00.