Convert time from MST to HST. Enter any time to see the equivalent HST time, compare current MST and HST times side by side, and find overlapping business hours for calls and meetings.
Use this MST to HST converter to compare US Mountain and United States time, check the 3 hours gap, and confirm the right slot for calls, handoffs, and deadlines. Good overlap starts around 12:00 PM MST / 9:00 AM HST.
Converting between Mountain Standard Time and Hawaii Standard Time means accounting for a 3 hours gap — here's how to do it in under 10 seconds with no sign-up.
Pick the date and time in Mountain Standard Time (UTC -7) that you want to convert. Hit "Now" to load the current mst time instantly, or use "+1h" to step forward and compare.
The equivalent Hawaii Standard Time (UTC -10) time appears immediately. Since hst is 3 hours behind of mst, most daytime conversions stay on the same calendar day.
Click "Copy Time" to grab the hst result for your calendar or message. Use "+1d" to check how the conversion shifts across dates — useful when Daylight Saving Time changes the gap.
When someone in United States suggests 12:00 PM mst, that's 9:00 AM hst. This converter shows the overlap so both sides agree on one slot — no back-and-forth.
Late-night mst times can land on a different date in hst because of the 3 hours offset. The converter labels "next day" or "previous day" next to the result so you never send a message a day early or miss a deadline.
Daylight Saving adjustments can widen or narrow the mst–hst gap by an hour. During transition weeks many people get it wrong. This converter pulls the current UTC offsets automatically, so the result is right even on the changeover day.
Product launches, sports matches, and webinars are often announced in mst. Convert the event time to hst so you know exactly when to tune in — with a 3 hours difference, a morning event in United States falls during work hours in United States.
Quick-reference conversion table covering every hour of the day at a glance.
Mountain Standard Time to Hawaii Standard Time full day schedule
| Mountain Standard Time | Hawaii Standard Time |
|---|---|
| 12:00 AM |
9:00 PM
(previous day)
|
| 1:00 AM |
10:00 PM
(previous day)
|
| 2:00 AM |
11:00 PM
(previous day)
|
| 3:00 AM |
12:00 AM
|
| 4:00 AM |
1:00 AM
|
| 5:00 AM |
2:00 AM
|
| 6:00 AM |
3:00 AM
|
| 7:00 AM |
4:00 AM
|
| 8:00 AM |
5:00 AM
|
| 9:00 AM |
6:00 AM
|
| 10:00 AM |
7:00 AM
|
| 11:00 AM |
8:00 AM
|
| 12:00 PM |
9:00 AM
|
| 1:00 PM |
10:00 AM
|
| 2:00 PM |
11:00 AM
|
| 3:00 PM |
12:00 PM
|
| 4:00 PM |
1:00 PM
|
| 5:00 PM |
2:00 PM
|
| 6:00 PM |
3:00 PM
|
| 7:00 PM |
4:00 PM
|
| 8:00 PM |
5:00 PM
|
| 9:00 PM |
6:00 PM
|
| 10:00 PM |
7:00 PM
|
| 11:00 PM |
8:00 PM
|
US Mountain — Denver, Salt Lake City, most of Arizona (Arizona notably observes no DST, so it's MST year-round while its neighbours flip). Business hours 9 AM – 5 PM MT.
Explore more mst conversions for major business and travel corridors. Each page includes a 24-hour chart, time difference summary, and meeting overlap guidance.
Find the time difference from any major zone into Hawaii Standard Time. Use these pages when scheduling with United States from a different region.
