Offset
The time difference between Greenwich Mean Time and Adelaide is 8.5 hours.
Greenwich Mean Time (BST) is behind Adelaide (ACST).
BST: UTC+1
ACST: UTC+9:30
Greenwich Mean Time is currently observing daylight saving time; Adelaide is not.
When to schedule
Standard business hours (9 AM–5 PM, Mon–Fri) in Greenwich Mean Time and Adelaide don't overlap on the same weekday. Adelaide is 9 hours ahead of Greenwich Mean Time.
With some flexibility, there’s a workable window outside standard hours:
- 7 AM–12 PM in Greenwich Mean Time (3 PM–8 PM in Adelaide) — suggest 9:00 AM Greenwich Mean Time (5:30 PM Adelaide).
This means an early start or late finish for one side, but it’s a reasonable slot for a one-off meeting.
This window may shift by an hour during daylight saving time.
Public holidays in 2026
National public holidays can affect availability — a counterpart is likely off work on their own holidays, so it's worth planning meetings and deadlines around them.
United Kingdom
- Good FridayFri, Apr 3
- Early May Bank HolidayMon, May 4
- Spring Bank HolidayMon, May 25
- Christmas DayFri, Dec 25
- St. Stephen's DayMon, Dec 28
Australia
- New Year's DayThu, Jan 1
- Australia DayMon, Jan 26
- Good FridayFri, Apr 3
- Easter MondayMon, Apr 6
- Christmas DayFri, Dec 25
- St. Stephen's DayMon, Dec 28
About these zones
Greenwich Mean Time is also known as GMT, or BST. To call United Kingdom, dial +44.
Adelaide uses Australian Central Time (ACST, or ACDT). To call Australia, dial +61.
Adelaide is approximately 10,100 miles east of Greenwich Mean Time.
Quick reference
Full 24-hour conversion table — tap any time to open it in the converter.
| GMT | Adelaide | Day |
|---|---|---|
| 12:00 am | 8:30 am | Same day |
| 1:00 am | 9:30 am | Same day |
| 2:00 am | 10:30 am | Same day |
| 3:00 am | 11:30 am | Same day |
| 4:00 am | 12:30 pm | Same day |
| 5:00 am | 1:30 pm | Same day |
| 6:00 am | 2:30 pm | Same day |
| 7:00 am | 3:30 pm | Same day |
| 8:00 am | 4:30 pm | Same day |
| 9:00 am | 5:30 pm | Same day |
| 10:00 am | 6:30 pm | Same day |
| 11:00 am | 7:30 pm | Same day |
| 12:00 pm | 8:30 pm | Same day |
| 1:00 pm | 9:30 pm | Same day |
| 2:00 pm | 10:30 pm | Same day |
| 3:00 pm | 11:30 pm | Same day |
| 4:00 pm | 12:30 am | +1 day |
| 5:00 pm | 1:30 am | +1 day |
| 6:00 pm | 2:30 am | +1 day |
| 7:00 pm | 3:30 am | +1 day |
| 8:00 pm | 4:30 am | +1 day |
| 9:00 pm | 5:30 am | +1 day |
| 10:00 pm | 6:30 am | +1 day |
| 11:00 pm | 7:30 am | +1 day |
Daylight saving time
Both zones observe daylight saving time, but they transition on different dates.
Greenwich Mean Time: next transition on Sunday, October 25, 2026.
Adelaide: next transition on Sunday, October 4, 2026.
Greenwich Mean Time and Adelaide are in opposite hemispheres, so their clocks change in opposite directions about six months apart — one springs forward while the other falls back. The offset between them therefore shifts twice a year and can swing by up to two hours across the seasons, more than a typical same-hemisphere pair. Recurring meetings will need re-checking after each transition.
See the daylight saving time page for transition dates across every time zone.
Daylight today
- Sunrise
- 4:47 AM
- Sunset
- 9:13 PM
- Day length
- 16h 25m
- Sunrise
- 7:18 AM
- Sunset
- 5:12 PM
- Day length
- 9h 54m
Cities in these zones
Cities in Greenwich Mean Time
Browse all cities to see the current local time anywhere.
Airports in these zones
Airports in Greenwich Mean Time
- LCY
- LGW
- LHR
- LTN
- STN
- BHX
- EMA
- GLA
- PIK
- LBA
Airports in Australian Central Time
- ADL
Related conversions
Common conversions
- What is 9:00 am GMT in Adelaide?
- 9:00 am GMT is 5:30 pm Adelaide.
- What is 12:00 pm GMT in Adelaide?
- 12:00 pm GMT is 8:30 pm Adelaide.
- What is 12:30 pm GMT in Adelaide?
- 12:30 pm GMT is 9:00 pm Adelaide.
- What is 2:00 pm GMT in Adelaide?
- 2:00 pm GMT is 10:30 pm Adelaide.
- What is 5:00 pm GMT in Adelaide?
- 5:00 pm GMT is 1:30 am Adelaide, the next day.
- What is 11:30 pm GMT in Adelaide?
- 11:30 pm GMT is 8:00 am Adelaide, the next day.