BST to MST Converter
Convert time between British Summer Time (BST) and Mountain Standard Time (MST)
British Summer Time (BST)
Mountain Standard Time (MST)
Time Difference
Mountain Standard Time (MST) is 0 hours ahead of British Summer Time (BST)
Select Date
Select Time
Quick Reference
| BST | MST |
|---|---|
| 02:00 | 19:00 |
| 04:00 | 21:00 |
| 06:00 | 23:00 |
| 08:00 | 01:00 |
| 10:00 | 03:00 |
| 12:00 | 05:00 |
| 14:00 | 07:00 |
| 16:00 | 09:00 |
| 18:00 | 11:00 |
| 20:00 | 13:00 |
| 22:00 | 15:00 |
| 00:00 | 17:00 |
Top 10 Most Common Time Zones
| Abbreviation | Full Name | UTC Offset | Typical Use |
|---|---|---|---|
| UTC | Coordinated Universal Time | UTC ±0 | Global reference standard (servers, logs, APIs) |
| EST / EDT | Eastern (US) Time | UTC −5 / −4 | New York, Toronto — North American business hub |
| CST / CDT | Central (US) Time | UTC −6 / −5 | Chicago, Dallas — US central business region |
| PST / PDT | Pacific (US) Time | UTC −8 / −7 | San Francisco, Los Angeles — tech industry standard |
| GMT / BST | Greenwich Mean / British Summer Time | UTC 0 / +1 | UK, used globally as a reference with UTC |
| CET / CEST | Central European (Summer) Time | UTC +1 / +2 | Paris, Berlin, Amsterdam — EU business core |
| IST | India Standard Time | UTC +5:30 | India — major IT & outsourcing region |
| CST | China Standard Time | UTC +8 | Beijing, Shanghai — East Asia business hub |
| JST | Japan Standard Time | UTC +9 | Tokyo — finance & tech hub |
| AEST / AEDT | Australian Eastern (Daylight) Time | UTC +10 / +11 | Sydney, Melbourne — APAC regional business |
Why Time Zone Abbreviations Are Ambiguous
Unlike standardized identifiers (like America/New_York or Europe/London from the IANA tz database), abbreviations such as "CST" or "IST" are not globally unique. They can refer to different time zones depending on context — country, region, or even time of year (due to daylight saving time).
Common Ambiguous Time Zone Abbreviations
| Abbrev. | Common Meaning(s) | UTC Offset | Region(s) |
|---|---|---|---|
| CST | Central Standard Time / China Standard Time / Cuba Standard Time | UTC−6 / UTC+8 / UTC−5 | North America, China, Cuba |
| IST | Indian Standard Time / Irish Standard Time / Israel Standard Time | UTC+5:30 / UTC+1 / UTC+2 | India, Ireland, Israel |
| AST | Atlantic Standard Time / Arabia Standard Time | UTC−4 / UTC+3 | Caribbean, Canada, Middle East |
| PST | Pacific Standard Time / Philippine Standard Time | UTC−8 / UTC+8 | North America, Philippines |
| EST | Eastern Standard Time (North America / Australia) | UTC−5 / UTC+10 | North America, Australia |
✅ Best Practice
To avoid ambiguity, always:
- Use IANA tz identifiers — e.g.,
America/New_Yorkinstead of "EST" - Specify UTC offset explicitly — e.g.,
UTC−5when abbreviations must be used - Include the full timezone name — e.g., "Eastern Standard Time (EST)" with UTC offset
Related Time Zone Conversions
About BST to MST Time Conversion
Converting time between British Summer Time (BST) and Mountain Standard Time (MST) is essential for coordinating activities between the UK and the US Mountain region during winter months. BST is UTC+1, while MST is UTC-7, making MST 8 hours behind BST.
This time zone converter uses the IANA timezone database to ensure accurate calculations, accounting for daylight saving time transitions and regional variations. Whether you're scheduling business meetings between London and Denver, planning travel, or coordinating with teams across time zones, our converter provides reliable results. Note that during summer months, the US Mountain region observes MDT (Mountain Daylight Time, UTC-6), which is 7 hours behind BST.
Common Use Cases for BST to MST Conversion
Business & Work
- Scheduling meetings between UK and US Mountain region offices
- Coordinating London and Denver business operations
- Planning transatlantic conference calls for Mountain Time Zone
Personal & Travel
- Planning travel itineraries from UK to US Mountain region
- Coordinating with family and friends in Denver, Salt Lake City, and Phoenix
- Scheduling virtual events with UK-US Mountain audiences
Time Zone Information
British Summer Time (BST)
- UTC Offset: UTC+1 (UTC+0 during GMT)
- IANA Timezone: Europe/London
- Daylight Saving: Last Sunday in March to Last Sunday in October
- Major Cities: London, Manchester, Edinburgh, Cardiff, Belfast
- Coverage: United Kingdom and Ireland (during daylight saving time)
Mountain Standard Time (MST)
- UTC Offset: UTC-7 (UTC-6 during MDT)
- IANA Timezone: America/Denver
- Daylight Saving: Second Sunday in March to First Sunday in November (observes MDT)
- Major Cities: Denver, Salt Lake City, Albuquerque, Las Vegas, Billings
- Coverage: Mountain region of United States and Canada (uses MDT in summer)
Quick Reference: BST to MST
Remember: MST is always 8 hours behind BST. In summer, the US Mountain region uses MDT (UTC-6), making the difference 7 hours.
Frequently Asked Questions
What is the time difference between BST and MST?
British Summer Time (BST) is UTC+1, while Mountain Standard Time (MST) is UTC-7. BST is 8 hours ahead of MST. This means when it's 6:00 PM in BST, it's 10:00 AM in MST. Note that MST is the standard time; the US Mountain region observes Mountain Daylight Time (MDT, UTC-6) during daylight saving time.
What's the difference between MST and MDT?
Mountain Standard Time (MST) is UTC-7 and is used during winter months (November to March). Mountain Daylight Time (MDT) is UTC-6 and is used during summer months (March to November). When the US Mountain region is in MDT (summer), the time difference from BST becomes 7 hours instead of 8. Always verify which is active when scheduling.
When should I use the BST to MST converter?
Use this converter when coordinating with the Mountain region of the US during winter months (November to March) when MST is active. The major Mountain Time Zone cities include Denver, Salt Lake City, Phoenix, and Las Vegas. If you're scheduling during summer months, use the BST to MDT converter for more accurate times.
What are the major cities in the MST timezone?
Major cities in the Mountain Standard Time zone include Denver (Colorado), Salt Lake City (Utah), Phoenix (Arizona), Las Vegas (Nevada), Albuquerque (New Mexico), and Billings (Montana). These are important business and technology centers in the US Mountain West region.
How do I convert BST to MST manually?
To convert from BST to MST, subtract 8 hours from the BST time. For example, if it's 6:00 PM BST, it would be 10:00 AM MST. Remember this only applies to winter months. During summer when the US Mountain region observes MDT, the difference is 7 hours instead. Always check the current date to use the correct conversion.
What should I know about scheduling across BST and MST?
The UK and US Mountain region have limited working hour overlap. Morning BST times (8-10 AM) correspond to late evening MST previous day (12-2 AM), making synchronous morning meetings difficult. Afternoon BST times (2-4 PM) correspond to early morning MST (6-8 AM). Late afternoon BST (5-6 PM) works best for morning MST meetings (9-10 AM). Successful scheduling requires flexibility from both parties.
Pro Tips
- • BST is 8 hours ahead of MST during winter months (November-March). Remember to switch to the BST to MDT converter when summer daylight saving time is active.
- • The UK observes daylight saving time with different dates than the US Mountain region. UK changes: last Sunday of March/October. US Mountain region: second Sunday of March/first Sunday of November.
- • Early morning BST (8-10 AM) equals late evening previous day MST (12-2 AM), making synchronous meetings very difficult without one party working overnight.
- • Afternoon BST (2-4 PM) roughly aligns with early morning MST (6-8 AM), which is the most practical window for transatlantic scheduling to avoid extreme hours.
- • Late afternoon UK times (5-6 PM BST) correspond to morning Mountain region times (9-10 AM MST), making this the ideal window for important cross-timezone meetings.
- • Arizona (Phoenix) does not observe daylight saving time, so it remains on MST year-round. Keep this in mind when scheduling meetings with Arizona-based contacts.