Self-Assessment – Mutual Fund

Dear Sir/Madam, I am a first-time tax payer who will start paying tax part-way in the tax year of 2022-23. Among other investment incomes, I hold two accumulation mutual funds that reinvest dividends as shares and I would like to know how to report the investment incomes from them. Do I report: (a) only the dividends that were re-invested after the day I become tax resident, and the capital gain (with the already-taxed dividends deducted) when I redeem the fund? (b) just the capital gain which will include the dividend reinvestments as and when I redeem the fund? Thank you.

Hi enquirer_2023June_HMRC,
If you qualify for split year then you only report any foreign income for the UK part of the year:
RDRM12000 - Residence: The SRT: Split year treatment: Contents.
If you do not qualify then you will need to report all your foreign income to the UK:
Tax on foreign income
The guidance at RDRM12150 at www.gov.uk will help you work out if split year treatment applies.
If this applies, then it is the dividends that you report. you will only have a capital gain when/if you sell.
Thank you.