London to Sydney Time Converter
Sydney is 10 hours ahead of London (GMT) in standard time. The gap varies 9–11 hours with seasonal DST in both countries.
Daylight saving note: Varies 9–11h depending on whether the UK (BST) or Sydney (AEDT) is on daylight saving.
GMT to AEST Conversion Table
Full 24-hour reference table. Use the live clocks above for the exact current offset.
| 🇬🇧 GMT | 🇦🇺 GMT → AESTUTC+0 to UTC+10 | 🇦🇺 BST → AESTUTC+1 to UTC+10 | 🇦🇺 GMT → AEDTUTC+0 to UTC+11 | Note |
|---|---|---|---|---|
| 00:00 | 10:00 AM | 9:00 AM | 11:00 AM | |
| 01:00 | 11:00 AM | 10:00 AM | 12:00 PM | |
| 02:00 | 12:00 PM | 11:00 AM | 1:00 PM | |
| 03:00 | 1:00 PM | 12:00 PM | 2:00 PM | |
| 04:00 | 2:00 PM | 1:00 PM | 3:00 PM | |
| 05:00 | 3:00 PM | 2:00 PM | 4:00 PM | |
| 06:00 | 4:00 PM | 3:00 PM | 5:00 PM | |
| 07:00 | 5:00 PM | 4:00 PM | 6:00 PM | |
| 08:00 | 6:00 PM | 5:00 PM | 7:00 PM | |
| 09:00 | 7:00 PM | 6:00 PM | 8:00 PM | |
| 10:00 | 8:00 PM | 7:00 PM | 9:00 PM | |
| 11:00 | 9:00 PM | 8:00 PM | 10:00 PM | |
| 12:00 | 10:00 PM | 9:00 PM | 11:00 PM | |
| 13:00 | 11:00 PM | 10:00 PM | 12:00 AM | next day |
| 14:00 | 12:00 AM | 11:00 PM | 1:00 AM | next day |
| 15:00 | 1:00 AM | 12:00 AM | 2:00 AM | next day |
| 16:00 | 2:00 AM | 1:00 AM | 3:00 AM | next day |
| 17:00 | 3:00 AM | 2:00 AM | 4:00 AM | next day |
| 18:00 | 4:00 AM | 3:00 AM | 5:00 AM | next day |
| 19:00 | 5:00 AM | 4:00 AM | 6:00 AM | next day |
| 20:00 | 6:00 AM | 5:00 AM | 7:00 AM | next day |
| 21:00 | 7:00 AM | 6:00 AM | 8:00 AM | next day |
| 22:00 | 8:00 AM | 7:00 AM | 9:00 AM | next day |
| 23:00 | 9:00 AM | 8:00 AM | 10:00 AM | next day |
* "next day" = converted time falls on the following calendar day.
Best Hours to Schedule London–Sydney Calls
The viable London–Sydney overlap is 7:00–9:00 AM London (5:00–7:00 PM Sydney). London arrives early; Sydney wraps up their day. A 8:00 AM London call is 6:00 PM Sydney — end of day for Australian colleagues.
About London (GMT)
London (GMT/BST) and Sydney (AEST/AEDT) both observe daylight saving, but in opposite seasons. When London is on BST (summer, UTC+1), the gap is 9 hours. When Sydney is on AEDT (October–April, UTC+11), the gap is 11 hours from GMT. Each DST shift by either city changes the conversion.
About Sydney (AEST)
Sydney (AEST, UTC+10) serves as Australia's financial capital. The London–Sydney corridor is one of the most active Commonwealth business relationships. Despite the 10-hour gap, both cities maintain significant bilateral trade in financial services, resources, and technology.
How to Avoid London–Sydney Conversion Mistakes
Use the live clocks and the table for different jobs. The live clocks show the current offset between London and Sydney. The table gives you a stable reference for planning common hours. If the page has more than one table column, pick the column that matches the season or DST state shown in the column label.
Daylight saving is the main trap. Some pairs stay fixed all year, while others move by one hour because only one side changes clocks, or because the two sides change on different dates. That is why this page keeps the daylight saving note near the live clocks and labels alternate table scenarios instead of hiding the offset change in a paragraph.
Always check the calendar date when the converted time lands near midnight. A late evening time in London can become the next day in Sydney, and an early morning time can still be the previous day. If the table marks "next day" or "prev day", include that date shift in the message or calendar invite.
Abbreviations can be ambiguous. ET can mean EST or EDT; London can be GMT or BST; Sydney can be AEST or AEDT. City names and IANA time zones are safer for exact scheduling than abbreviations alone. For recurring meetings, test the same local time once in January and once in July before you lock it in.
For one-off events, enter the exact date and time in the main time zone converter or meeting scheduler if the table does not show your hour. That keeps the answer tied to the correct daylight saving rule instead of a memorized offset.
When you share the result, write both local times in one line: "10:00 AM GMT/ converted AEST time." For client calls, flights, webinars, launches, and deadlines, also include the date. The extra wording feels repetitive, but it gives every recipient a second way to catch a timezone mistake before it becomes a missed meeting. It is especially helpful when someone forwards the invite to a third city.
Frequently Asked Questions
How many hours ahead is Sydney from London?
Sydney is 10 hours ahead of London (GMT) in winter. The gap is 9 hours when London is on BST and 11 hours when Sydney is on AEDT (from GMT).
What time is 8 AM London in Sydney?
8:00 AM London (GMT) is 6:00 PM Sydney (AEST). During UK BST, 8:00 AM BST is 5:00 PM Sydney.
What is the best overlap for London-Sydney calls?
The best slot is 7:00–9:00 AM London (5:00–7:00 PM Sydney). Outside this 2-hour window, one city is outside normal working hours.
Does Australia observe daylight saving?
Yes, but in the Southern Hemisphere summer (October–April). Sydney (NSW) switches to AEDT (UTC+11) in October and reverts to AEST (UTC+10) in April — the inverse of the UK schedule.