| IB Results Release | 04 Jan |
| Y1 – IB1 School Camp | 06 – 07 Jan |
| Y1 Induction Ceremony | 14 Jan |
| IGCSE Results Release | 18 Jan |
| Chinese New Year Celebration | 28 Jan |
| HCIS Model United Nations | 08 – 09 Mar |
| Hwa Chong Founders’ Day Prize-Giving Ceremony | 11 Mar |
| HCIS Open House | 02 Apr |
| Blood Donation Drive | 12 Apr |
| TEDx Youth and TOK Seminars | 21 Apr |
| Y1 – IB1 Mid-Year Examinations | 28 Apr – 10 May |
| Y1 – Y4 Sabbatical Programme | 17 May – 26 May |
| Y1 – IB2 Parent-Teacher Interaction | 27 May |
| IB2 Mid-Year Examinations | 27 Jun – 01 Jul |
| The Voice of HCIS | 05 Aug |
| HCIS Gives Back | 08 Aug |
| Y4 (IGCSE) Preliminary Examinations | 16 Aug – 31 Aug |
| Y1 – Y4 Parent-Teacher Interaction | 20 Aug |
| IB2 Preliminary Examinations | 29 Aug – 31 Aug, 12 Sep – 23 Sep |
| Teachers’ Day Celebration | 01 Sep |
| IB 1 End-of-Year Examinations | 12 Sep – 23 Sep |
| IGCSE Commencement Day | 04 Oct |
| IGCSE Examinations | 05 Oct – 17 Nov |
| IB Graduation | 07 Oct |
| IB Examinations | 24 Oct – 09 Nov |
| Y1 – Y4 End-of-Year Examinations | 25 Oct – 04 Nov |
| IB1 CAS Day | 04 Nov (TBC) |
| Examination Marking Day | 07 – 08 Nov |
| Innofest | 16 Nov |