File your company's first CT600 after incorporation
Taxley files a company's first CT600 after incorporation, with the first accounts and tax computation, and starts the accounts on the date of incorporation even when the return starts later, when trading began. If the company had income or costs before the return's period starts, contact support before you file, and if the first accounts don't start on the date of incorporation, you file them at Companies House yourself.
Preparing and previewing is free. You pay one fee per return, only when you choose to file.
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What can't Taxley do with a company's first CT600?
A few first returns need more than Taxley does today.
- Income or costs before the return starts. If the accounts start on the date of incorporation but the company had income or costs before its tax return's period starts, contact support before you file. Taxley doesn't split those days out for you.
- First accounts that start later. A company's first accounts must start on the date of incorporation. If yours don't, Taxley files the CT600 only, and you file the first accounts at Companies House yourself; the filing page gives the deadline.
- Accounts longer than 18 months. A period of account can't be longer, so Taxley won't start a return for one.
- Older periods. Some earlier accounting periods. Before you pay, Taxley checks whether it can file yours.
- Advice. Taxley is software from Taxley UK LLP, not an accountant or tax agent. It doesn't decide when the company started trading; you enter the dates.
How do you file a first CT600 with Taxley?
The first accounts start on the date of incorporation, and the first return starts when the company started trading. When the dates differ, the first return goes to HMRC with accounts that start earlier, on the date of incorporation (GOV.UK: your limited company's first accounts and Company Tax Return).
- Find the company on the register. Taxley copies its name, number, date of incorporation and directors from Companies House.
- Set the dates. Enter the period the return covers. When Companies House shows the first accounts starting earlier, Taxley starts the accounts on that date for you; otherwise use "Change" beside the accounting period.
- Enter the figures. Income, costs and the balance sheet at the end of the first period. First accounts have no earlier year to compare with.
- Check and pay. You see the CT600, the computation and the accounts before you pay. Then Taxley sends the return to HMRC with the company's own Government Gateway login.
- File the first accounts at Companies House. Once the return is paid and finished, press "File accounts at Companies House" and enter the company's 6-character authentication code.
A first period longer than 12 months needs two returns: see two CT600s for a first accounting period over 12 months.
When are the first return, the tax and the first accounts due?
The CT600 is due 12 months after the end of the accounting period, and the tax 9 months and 1 day after it. When the first accounts run longer than 12 months and need two CT600s, both returns are due 12 months after the accounts end, and each period's tax is due 9 months and 1 day after that period ends. Companies House usually wants the first accounts 21 months after the date of incorporation, a separate deadline. The free Corporation Tax deadline calculator gives the dates for your period, and the filing page shows the Companies House date.
What does it cost to file a first CT600 with Taxley?
The same as any return: £49.95 with micro-entity accounts or £139 with small-company accounts. If the first period becomes two returns, one fee covers both. A dormant company's nil return costs £9.50. Every plan is on the pricing page.
Frequently asked questions
When does a company's first accounting period start?
For Corporation Tax, when the company starts trading or otherwise comes within the charge to tax, which can be later than incorporation. The first accounts still start on the date of incorporation. Taxley lets the accounts start earlier than the return, so the first return goes to HMRC with the whole of the first accounts.
What do I need before I file the first return?
The company's 10-digit Unique Taxpayer Reference (UTR) from HMRC, the company's Government Gateway user ID and password for Corporation Tax, and the figures from its records. To file the accounts at Companies House you also need its 6-character authentication code.
What if the company didn't trade at first?
A company is usually dormant for Corporation Tax until it starts trading, and HMRC expects a return for that time only if it sends a notice to deliver one. Taxley files dormant nil returns as well as trading returns.
What is the Companies House deadline for first accounts?
Usually 21 months after the date of incorporation, separately from the CT600 deadline. Taxley files the first accounts there once the return is paid and finished, if they start on the date of incorporation, and the filing page shows the deadline.
Does Taxley carry the figures into the second year?
Yes. Once the first return is filed, the next year's return starts with the first year's closing balance sheet and any unused losses, and the second accounts show the first year's figures alongside.
Ready to file your first return?
Find the company on the register, enter the first period's figures, and pay only when you file.