How many hours is HST behind CST?
As abbreviations, CST is always 4 hours ahead of HST: HST is UTC−10 and CST is UTC−6. To convert, add 4 hours.
Check which label you actually need: CST (Central Time is on CDT today). A time written with an abbreviation that is not in use is usually meant as the local time, so convert between the places instead: right now CST is 5 hours ahead of HST.
When the HST to CST time difference changes
For most of the year CST is 5 hours ahead of HST. From 1 November to 31 December 2026, CST is 4 hours ahead of HST instead, because the two places change their clocks on different dates. Meetings booked by the usual gap land an hour off in those weeks.
| Dates | CST vs HST | Length |
|---|---|---|
| 8 March 2026 to 31 October 2026 | 5 hours ahead | 238 days |
| 1 November 2026 to 31 December 2026 | 4 hours ahead | 61 days |
| 1 January 2027 to 13 March 2027 | 4 hours ahead | 72 days |
| 14 March 2027 to 6 November 2027 | 5 hours ahead | 238 days |
| 7 November 2027 to 31 December 2027 | 4 hours ahead | 55 days |
Calling hours for HST and CST
- When CST is 5 hours ahead of HST: 3 shared office hours, 09:00 to 12:00 in HST (14:00 to 17:00 in CST).
- When CST is 4 hours ahead of HST: 4 shared office hours, 09:00 to 13:00 in HST (13:00 to 17:00 in CST).