London to Sydney
+11hLondon
GMTSOURCESydney
AESTGreen rows indicate typical business hours (9 AM - 5 PM)
GMT and AEST on the World Map
The map below highlights the GMT (Greenwich Mean Time) and AEST (Australian Eastern Standard Time) timezone regions across the globe.
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.
AEST – Australian Eastern Standard Time
UTC+10:00Australian Eastern Standard Time (AEST) covers eastern Australia, 10 hours ahead of UTC.
- •Queensland does not observe daylight saving time, staying on AEST year-round.
- •Sydney and Melbourne switch to AEDT (UTC+11:00) in summer.
- •The Australian Securities Exchange (ASX) operates on AEST/AEDT.
- •AEST is 15 hours ahead of EST during winter.
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.
London was the first city to have an underground railway, opening in 1863.
About Sydney
WikipediaSydney operates on Australian Eastern Standard Time (AEST/AEDT). As Australia's financial capital, Sydney opens global markets at the start of the business day.
Sydney Opera House took 16 years to build and its roof is covered with over 1 million tiles.
Time Conversion Guide: London to Sydney
London, UK operates on the Greenwich Mean Time (UTC+00:00). Sydney, Australia uses Australian Eastern Standard Time (UTC+10:00).
The time difference between London and Sydney is 660 minutes (+11h). When it's noon in London, it's 11:00 PM in Sydney.
Why Convert London to Sydney Time?
Whether you're traveling from London to Sydney or simply need to coordinate across time zones, understanding the 11-hour difference is key. Use this converter to quickly determine the current time in Sydney and ensure your schedule aligns perfectly.
Remember: Daylight Saving Time changes can affect the time difference between London and Sydney. Always double-check the current offset before scheduling important events.
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.
About AEST (Australian Eastern Standard Time)
Australian Eastern Standard Time (AEST) is used in the eastern states of Australia including New South Wales, Victoria, Queensland, Tasmania, and the ACT. During summer (October to April), NSW, VIC, TAS, and ACT switch to Australian Eastern Daylight Time (AEDT, UTC+11:00), while Queensland remains on AEST year-round.
Best Time to Call Between London and Sydney
If you want to reach someone in Sydney during standard business hours (9 AM – 5 PM AEST), the best time to call from London would be:
- Sydney 9:00 AM = London 10:00 PM
- Sydney 12:00 PM = London 01:00 AM
- Sydney 5:00 PM = London 06:00 AM
Business Hours Overlap
London and Sydney have minimal business hours overlap due to the +11h time difference. Teams may need to schedule early morning or late evening meetings for real-time collaboration.
To wrap up, keeping track of the +11h gap between London and Sydney is essential for seamless communication. Bookmark this converter to stay on top of your schedule.
🕐 Daylight Saving Time Info
London
❄ Currently in Standard Time
Standard: UTC+00:00 · DST: UTC+01:00
Clocks spring forward on Sun, Mar 29, 2026
Sydney
☀ Currently in DST
Standard: UTC+10:00 · DST: UTC+11:00
Clocks fall back on Sat, Apr 4, 2026
⚠ These locations are currently in different DST states, so the time difference may change when clocks adjust.
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 London and Sydney?
Sydney is +11h from London.
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 timezone is Sydney in?
Sydney operates on Australian Eastern Standard Time (AEST/AEDT). As Australia's financial capital, Sydney opens global markets at the start of the business day.
What are the business hours in London?
Standard business hours in London are 9:00 AM - 5:00 PM GMT.
What are the business hours in Sydney?
Standard business hours in Sydney are 9:00 AM - 5:00 PM AEST.
What is the best time to schedule a call between London and Sydney?
The best overlap for a call is when both cities are in business hours. London works 9:00 AM - 5:00 PM GMT and Sydney works 9:00 AM - 5:00 PM AEST (+11h difference). Try scheduling during the overlapping window for maximum convenience.
What currencies are used in London and Sydney?
London uses GBP (£) while Sydney uses AUD (A$). Check current exchange rates when planning travel or business between these cities.
How do London and Sydney compare in size?
London has a population of approximately 8.8 million (metro: 14.8 million), while Sydney has approximately 5.4 million (metro: 5.4 million).
What are the major landmarks in London and Sydney?
London is known for Big Ben, Tower Bridge, Buckingham Palace. Sydney is famous for Sydney Opera House, Sydney Harbour Bridge, Bondi Beach.
Do London and Sydney have stock exchanges?
Yes. London has the LSE (London Stock Exchange) and Sydney has the ASX (Australian Securities Exchange). The +11h time difference affects trading hour overlaps between these exchanges.
Which countries use GMT (Greenwich Mean Time)?
GMT is used in United Kingdom, Ireland, Iceland, Portugal (mainland), Ghana, Senegal, and 9 more countries.
Does GMT observe daylight saving time?
Yes, GMT switches to BST during summer months.
What are some interesting facts about GMT?
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.
Which cities are in the AEST timezone?
Major cities in the AEST timezone include Sydney, Melbourne, Brisbane, Canberra, Hobart, Gold Coast.
What is the UTC offset for AEST?
Australian Eastern Standard Time (AEST) is at UTC+10:00. During daylight saving time, it shifts to AEDT.
What should I know about the AEST timezone?
Queensland does not observe daylight saving time, staying on AEST year-round. Sydney and Melbourne switch to AEDT (UTC+11:00) in summer.
When is it midnight in London, what time is it in Sydney?
When it is 12:00 AM (midnight) in London (GMT), it is +11h later in Sydney (AEST).
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