How many hours is MST behind NZDT?
As abbreviations, NZDT is always 20 hours ahead of MST: MST is UTC−7 and NZDT is UTC+13. To convert, add 20 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 NZDT is 19 hours ahead of MST.
When the MST to NZDT time difference changes
For most of the year NZDT is 18 hours ahead of MST. From 27 September to 31 October 2026, NZDT is 19 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 | NZDT vs MST | Length |
|---|---|---|
| 27 September 2026 to 31 October 2026 | 19 hours ahead | 35 days |
| 1 November 2026 to 31 December 2026 | 20 hours ahead | 61 days |
| 1 January 2027 to 13 March 2027 | 20 hours ahead | 72 days |
| 14 March 2027 to 3 April 2027 | 19 hours ahead | 21 days |
| 4 April 2027 to 25 September 2027 | 18 hours ahead | 175 days |
| 26 September 2027 to 6 November 2027 | 19 hours ahead | 42 days |
| 7 November 2027 to 31 December 2027 | 20 hours ahead | 55 days |
Calling hours for MST and NZDT
- When NZDT is 18 hours ahead of MST: no shared 09:00 to 17:00 hours; one side has to take the call outside office hours.
- When NZDT is 20 hours ahead of MST: no shared 09:00 to 17:00 hours; one side has to take the call outside office hours.
- When NZDT is 19 hours ahead of MST: no shared 09:00 to 17:00 hours; one side has to take the call outside office hours.