Split year treatment

Hi, I moved to UK on Jun 2023 and I got a salary on Apr 2023 in Hong Kong. Also, I got a job in UK that started on Jan 2024. Someone told me that I have to apply Split year treatment. 1) Is it necessary to apply split year treatment? 2)If I have to do the split year and missed the deadline for paper form. What should I do?

Hi
If you qualify for split year then you only report any foreign income for the UK part of the year. You can see guidance here:
RDRM12000 - Residence: The SRT: Split year treatment
If you do not qualify then you will need to report all your foreign income to the UK. Again, you can see guidance here:
Tax on foreign income  
The guidance below will help you work out if split year treatment applies:  
RDRM12150 - Residence: The SRT: Split year treatment: Case 4: Starting to have a home in the UK only
You can purchase 3rd party software to file the return online tp include the resdience section
Thank you.