CT rate FY2023

I'm trying to submit co accounts and CT return online. Accounting period is 1/9/22 - 31/8/23 - return splits into two FY but both are being taxed at 19% rather than 19% and 25%. Marginal relief is being correctly applied. Is there a fault in the system? Should I submit and expect return to be corrected? Thanks

Hi MPW,
I am not aware of any fault within the HMRC system in relation to 'Marginal Relief'.
I would refer you to:
Marginal Relief for Corporation Tax
Where you will find a marginal relief calculator
Click on - calculate Marginal Relief for Corporation Tax (CT)
If you believe an error has been made please contact CT Services on 0300 200 3410.
Corporation Tax: general enquiries
Thank you.