Honolulu to London
+10hHonolulu
HSTSOURCELondon
GMTGreen rows indicate typical business hours (9 AM - 5 PM)
HST and GMT on the World Map
The map below highlights the HST (Hawaii Standard Time) and GMT (Greenwich Mean Time) timezone regions across the globe.
HST – Hawaii Standard Time
UTC-10:00Hawaii Standard Time (HST) is the time zone for the Hawaiian Islands, 10 hours behind UTC.
- •Hawaii does not observe daylight saving time.
- •HST is 5 hours behind EST in winter and 6 hours behind EDT in summer.
- •Hawaii is one of only two US states that don't observe DST (the other is Arizona).
GMT – Greenwich Mean Time
UTC+00:00Greenwich Mean Time (GMT) is the mean solar time at the Royal Observatory in Greenwich, London. It is the same as UTC+00:00.
- •GMT is based on the Prime Meridian (0° longitude) passing through Greenwich, London.
- •The Royal Observatory in Greenwich has been the reference point for GMT since 1884.
- •GMT and UTC are often used interchangeably, but UTC is based on atomic clocks.
- •Iceland uses GMT year-round and never observes daylight saving time.
- •The UK switches from GMT to BST (British Summer Time) in late March each year.
About Honolulu
WikipediaHonolulu operates on Hawaii Standard Time (HST), UTC-10 with no daylight saving. Hawaii's consistent time makes it a predictable connection between Asia and mainland USA.
Honolulu is the southernmost major U.S. city.
About London
WikipediaLondon, where Greenwich Mean Time (GMT) originates, is the world's leading financial center alongside New York. The city bridges European and American business hours.
Greenwich Mean Time (GMT) is defined by the Prime Meridian at the Royal Observatory in Greenwich, London.
Understanding the Time Gap: Honolulu vs London
Honolulu, USA operates on the Hawaii Standard Time (UTC-10:00). London, UK uses Greenwich Mean Time (UTC+00:00).
The time difference between Honolulu and London is 600 minutes (+10h). When it's noon in Honolulu, it's 10:00 PM in London.
Why Convert Honolulu to London Time?
Navigating the time gap between Honolulu and London requires careful planning. With a difference of 10 hours, finding a suitable time for both locations is essential for effective collaboration. This tool simplifies the process, allowing you to instantly see the corresponding time in London.
Pro Tip: If you frequently communicate with people in London from Honolulu, consider adding a dual-clock widget to your phone or computer to keep track of the 10-hour difference at a glance.
About HST (Hawaii Standard Time)
Hawaii Standard Time (HST) is used in the state of Hawaii and does not observe daylight saving time. This makes HST one of the most consistent time zones in the US. The Hawaiian Islands are among the last places on Earth to see a new calendar day.
About GMT (Greenwich Mean Time)
Greenwich Mean Time (GMT) is the clock time at the Royal Observatory in Greenwich, London, which sits on the Prime Meridian (0° longitude). GMT serves as the reference point from which all other time zones are calculated. The United Kingdom uses GMT during winter months and switches to British Summer Time (BST, UTC+01:00) from late March to late October. Several West African nations use GMT year-round. GMT is often used interchangeably with UTC (Coordinated Universal Time), although technically they are different – UTC is based on atomic clocks while GMT is based on Earth's rotation.
Best Time to Call Between Honolulu and London
If you want to reach someone in London during standard business hours (9 AM – 5 PM GMT), the best time to call from Honolulu would be:
- London 9:00 AM = Honolulu 11:00 PM
- London 12:00 PM = Honolulu 02:00 AM
- London 5:00 PM = Honolulu 07:00 AM
Business Hours Overlap
Honolulu and London have minimal business hours overlap due to the +10h time difference. Teams may need to schedule early morning or late evening meetings for real-time collaboration.
To wrap up, keeping track of the +10h gap between Honolulu and London is essential for seamless communication. Bookmark this converter to stay on top of your schedule.
🕐 Daylight Saving Time Info
Honolulu
Does not observe DST
London
❄ Currently in Standard Time
Standard: UTC+00:00 · DST: UTC+01:00
Clocks spring forward on Sun, Mar 29, 2026
Learn More About Time
Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:
Frequently Asked Questions
What is the time difference between Honolulu and London?
London is +10h from Honolulu.
What timezone is Honolulu in?
Honolulu operates on Hawaii Standard Time (HST), UTC-10 with no daylight saving. Hawaii's consistent time makes it a predictable connection between Asia and mainland USA.
What timezone is London in?
London, where Greenwich Mean Time (GMT) originates, is the world's leading financial center alongside New York. The city bridges European and American business hours.
What are the business hours in Honolulu?
Standard business hours in Honolulu are 8:00 AM - 5:00 PM HST.
What are the business hours in London?
Standard business hours in London are 9:00 AM - 5:00 PM GMT.
What is the best time to schedule a call between Honolulu and London?
The best overlap for a call is when both cities are in business hours. Honolulu works 8:00 AM - 5:00 PM HST and London works 9:00 AM - 5:00 PM GMT (+10h difference). Try scheduling during the overlapping window for maximum convenience.
What currencies are used in Honolulu and London?
Honolulu uses USD ($) while London uses GBP (£). Check current exchange rates when planning travel or business between these cities.
How do Honolulu and London compare in size?
Honolulu has a population of approximately 350,000 (metro: 1 million), while London has approximately 8.8 million (metro: 14.8 million).
What are the major landmarks in Honolulu and London?
Honolulu is known for Waikiki Beach, Diamond Head, Pearl Harbor. London is famous for Big Ben, Tower Bridge, Buckingham Palace.
Do Honolulu and London have stock exchanges?
Yes. Honolulu has the N/A (Uses NYSE/NASDAQ) and London has the LSE (London Stock Exchange). The +10h time difference affects trading hour overlaps between these exchanges.
Which countries use HST (Hawaii Standard Time)?
HST is used in United States (Hawaii).
Does HST observe daylight saving time?
No, HST does not observe daylight saving time and remains at UTC-10:00 year-round.
What are some interesting facts about HST?
Hawaii does not observe daylight saving time. HST is 5 hours behind EST in winter and 6 hours behind EDT in summer.
Which cities are in the GMT timezone?
Major cities in the GMT timezone include London, Dublin, Lisbon, Accra, Reykjavik, Edinburgh, Casablanca, Dakar.
What is the UTC offset for GMT?
Greenwich Mean Time (GMT) is at UTC+00:00. During daylight saving time, it shifts to BST.
What should I know about the GMT timezone?
GMT is based on the Prime Meridian (0° longitude) passing through Greenwich, London. The Royal Observatory in Greenwich has been the reference point for GMT since 1884.
When is it midnight in Honolulu, what time is it in London?
When it is 12:00 AM (midnight) in Honolulu (HST), it is +10h later in London (GMT).
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