✔ 最佳答案
1. First of all, you need to check whether the charitable institution is approved by IRD. You can check in IRD's website
www.ird.gov.hk/chi/tax/ach_index.htm;
2. Assuming the charitable institution is approved by IRD. The maximum amount for tax deduction is 25% of your assessable income or profits and the aggregate amount for the year of assessment must be at least HK$100 (minimum).
3. In your case, the total amount should be filled in your tax return is HK$600 (HK$50 x 12 months if it is for full year).