How many hours is MST behind ChST?
As abbreviations, ChST is always 17 hours ahead of MST: MST is UTC−7 and ChST is UTC+10. To convert, add 17 hours.
Check which label you actually need: MST (Mountain Time is on MDT 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 ChST is 16 hours ahead of MST.
When the MST to ChST time difference changes
For most of the year ChST is 16 hours ahead of MST. From 1 November to 31 December 2026, ChST is 17 hours ahead of MST 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 | ChST vs MST | Length |
|---|---|---|
| 8 March 2026 to 31 October 2026 | 16 hours ahead | 238 days |
| 1 November 2026 to 31 December 2026 | 17 hours ahead | 61 days |
| 1 January 2027 to 13 March 2027 | 17 hours ahead | 72 days |
| 14 March 2027 to 6 November 2027 | 16 hours ahead | 238 days |
| 7 November 2027 to 31 December 2027 | 17 hours ahead | 55 days |
Best time for a meeting between MST and ChST
- When ChST is 16 hours ahead of MST: no shared 09:00 to 17:00 hours; try 17:00 in MST (09:00 in ChST).
- When ChST is 17 hours ahead of MST: no shared 09:00 to 17:00 hours; one side has to take the call outside office hours.