| Commencement of School and IB Results Release | 03 Jan |
| Y1 – IB1 School Camp | 05 – 06 Jan |
| Y1 Induction Ceremony | 13 Jan |
| IGCSE Results Release | 18 Jan |
| Chinese New Year Celebration | 20 Jan |
| Lohei Lunch | 02 Feb |
| Y1 Parent-Teacher Interaction | 03 Mar |
| Hwa Chong Founders’ Day Prize-Giving Ceremony | 10 Mar |
| HCIS Open House | 01 Apr |
| Combined Leadership Investiture | 12 Apr |
| IB2 Parent-Teacher Interaction | 13 Apr |
| Y1 – IB1 Mid-Year Examinations | 27 Apr – 09 May |
| Y1 – Y4 Sabbatical Programme / Internationalism Trips | 16 May – 25 May |
| Y1 – IB2 Parent-Teacher Interaction | 26 May |
| IB2 Mid-Year Examinations | 26 Jun – 30 Jun |
| Y4 IGCSE and IB2 Parent-Teacher Interaction | 27 Jul |
| The Voice of HCIS | 04 Aug |
| HCIS Gives Back | 08 Aug |
| Y4 (IGCSE) Preliminary Examinations | 16 Aug – 31 Aug |
| Y1 – IB1 Parent-Teacher Interaction | 18 Aug |
| IB2 Preliminary Examinations | 28 Aug – 30 Aug, 11 Sep – 22 Sep |
| Teachers’ Day Celebration | 31 Aug |
| IB1 End-of-Year Examinations | 11 Sep – 22 Sep |
| IGCSE Graduation Ceremony | 03 Oct |
| IB2 Graduation Ceremony | 06 Oct |
| IB Examinations | TBC |
| Y1 – Y4 End-of-Year Examinations | 19 Oct – 01 Nov |
| Innofest | 15 Nov |