How do I complete the CT600 for a long period of accounts? (Business users)

If your accounts cover a period of more than 12 months, you'll need to complete the CT600 for two periods, as follows:

1. Prepare the accounts for the full period and generate an XBRL version or PDF-with explanation (if required).
2. Apportion the profit/loss into a 12-month period and the remaining days – using days meets the HMRC guidelines.
3. Create the first (12-month) period return in TaxCalc (see instructions below).
4. Create the second (short) period return in TaxCalc (see instructions below).
5. Contact Support to resolve the filing restriction message.

How to create the first period return

1. Open TaxCalc 2024.
2. Click on Create a New CT600 Corporation.
3. Click on SimpleStep.
4. Go to CT600 Full/Short or Core > Return Period.
5. Enter the 12-month period.
6. Go to Accounts and Computations.
7. Under I am attaching Accounts..., tick Relating to a different period.
8. Enter the apportioned figures into Computations.
9. Complete the rest of the return.
10. Attach the XBRL accounts (for the full period).

How to create the second period return

1. Open TaxCalc 2024.
2. Click on Import Returns from TaxCalc 2023.
3. Browse and select the 12-month period you just created.
4. Open the return.
5. Click on Simple Step.
6. Go to CT600 Full/Short or Core> Return Period.
7. Enter the remaining period.
8. Go to Accounts and Computations.
9. Under I am attaching Accounts..., untick both Relating to this period and Relating to a different period.
10. Select Submitted with accompanying return from the drop-down menu – you don't need to send the accounts again.
11. Enter the apportioned figures into Computations.
12. Complete the rest of the return.