MDT to BST Converter
Convert time between Mountain Daylight Time (MDT) and British Summer Time (BST)
Mountain Daylight Time (MDT)
British Summer Time (BST)
Time Difference
British Summer Time (BST) is 0 hours ahead of Mountain Daylight Time (MDT)
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Select Time
Quick Reference
| MDT | BST |
|---|---|
| 19:00 | 02:00 |
| 21:00 | 04:00 |
| 23:00 | 06:00 |
| 01:00 | 08:00 |
| 03:00 | 10:00 |
| 05:00 | 12:00 |
| 07:00 | 14:00 |
| 09:00 | 16:00 |
| 11:00 | 18:00 |
| 13:00 | 20:00 |
| 15:00 | 22:00 |
| 17:00 | 00:00 |
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 MDT to BST Time Conversion
Converting time between Mountain Daylight Time (MDT) and British Summer Time (BST) is essential for coordinating business operations between the US Mountain region and the United Kingdom during summer months. MDT is UTC-6 (used March to November), while BST is UTC+1 (used late March to late October in the UK). BST is 7 hours ahead of MDT.
This conversion is important for companies with offices in Denver, Salt Lake City, and UK cities like London, Manchester, and Edinburgh. Both regions observe daylight saving time during overlapping periods, maintaining a consistent 7-hour difference. The coordination becomes more challenging during the few weeks when one region has switched to or from daylight saving time while the other has not, creating an 8-hour difference.
Common Use Cases for MDT to BST Conversion
Business & Work
- Scheduling meetings between US Mountain region and UK offices during summer months
- Coordinating international business operations with UK-based partners
- Managing software development and tech teams spanning Mountain US and UK
- Planning conference calls and webinars with UK participants
Personal & Travel
- Coordinating with family and friends in the UK
- Planning travel between Mountain US and the United Kingdom
- Scheduling virtual meetings with UK contacts and colleagues
- Arranging online collaboration with UK-based team members
Time Zone Information
Mountain Daylight Time (MDT)
- UTC Offset: UTC-6 (UTC-7 during MST)
- IANA Timezone: America/Denver
- Daylight Saving: Second Sunday in March to First Sunday in November
- Major Cities: Denver, Salt Lake City, Albuquerque, Boise, Fort Collins
- Coverage: Mountain United States and parts of Canada (summer months)
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, Birmingham, Edinburgh, Cardiff
- Coverage: United Kingdom including England, Scotland, Wales, and Northern Ireland (summer months)
Quick Reference: MDT to BST
BST is 7 hours ahead of MDT. This conversion applies during the overlapping summer period (approximately late March to late October) when both US Mountain region and UK are on daylight saving time. The 7-hour difference remains constant throughout this period, though it temporarily changes to 8 hours during the brief windows when DST transitions occur on different dates.
Frequently Asked Questions
What is the time difference between MDT and BST?
Mountain Daylight Time (MDT) is UTC-6, while British Summer Time (BST) is UTC+1. This means BST is 7 hours ahead of MDT. When it's 9:00 AM in Denver (MDT), it's 4:00 PM the same day in London (BST).
When are both MDT and BST active simultaneously?
Both timezones overlap during spring and early autumn. The US Mountain region switches to MDT on the second Sunday in March, while the UK switches to BST on the last Sunday in March. Both switch back in late October/early November, with the UK changing first (last Sunday in October).
Why is MDT to BST the primary summer US Mountain-UK conversion?
MDT and BST are both active for approximately 7 months (late March through late October), making this the primary conversion needed for summer coordination. The 7-hour difference remains constant throughout this entire period since both regions are on daylight saving time simultaneously.
What are the best times for MDT-BST business calls?
With a 7-hour difference, there is reasonable overlap. Early morning MDT (6-8 AM) corresponds to afternoon BST (1-3 PM) - good for morning meetings on both sides. Late morning MDT (10-11 AM) catches late afternoon BST (5-6 PM). Early afternoon MDT (2-3 PM) reaches evening BST (9-10 PM).
Which countries use British Summer Time?
BST is used in the United Kingdom and several British Overseas Territories. Major areas include England, Scotland, Wales, Northern Ireland, plus territories like Gibraltar, and the Isle of Man. During winter, these regions switch to GMT (UTC+0), creating an 8-hour difference with the US Mountain region.
How does the 7-hour gap affect US-UK business coordination?
The 7-hour offset creates good opportunities for real-time collaboration. UK mornings (9-12 PM BST) align with US Mountain evenings (2-5 PM MDT). This makes MDT-BST coordination easier than many other transatlantic pairings. Teams can achieve 2-3 hours of productive overlap during standard business hours.
Pro Tips
- • The 7-hour MDT to BST gap is consistent late March-October. Schedule key meetings for 10-11 AM MDT (5-6 PM BST) for end-of-UK-day discussions.
- • Denver 6 AM MDT = London 1 PM BST - perfect for early Mountain team standup with mid-day UK participation.
- • UK morning (9 AM BST) = 2 AM MDT - early but workable for urgent matters requiring same-day coordination.
- • Avoid scheduling after 4 PM MDT (11 PM BST) as UK staff are finishing their workday or already offline.
- • For daily standups, 10 AM MDT (5 PM BST) works well - late morning for Mountain, early evening for UK teams.
- • Mark late October and early November - UK switches back to GMT first, briefly changing offset to 8 hours before US Mountain region changes.
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