Offset
The time difference between Colombo and Central Time is 10.5 hours.
Colombo (IST) is ahead of Central Time (CDT).
IST: UTC+5:30
CDT: UTC-5
Central Time is currently observing daylight saving time; Colombo is not.
When to schedule
Standard business hours (9 AM–5 PM, Mon–Fri) in Colombo and Central Time don't overlap on the same weekday. Central Time is 10 hours behind Colombo.
With some flexibility, there’s a workable window outside standard hours:
- 6 PM–8 PM in Colombo (7 AM–9 AM in Central Time) — suggest 7:00 PM Colombo (8:30 AM Central Time).
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 States
- New Year's DayThu, Jan 1
- Martin Luther King, Jr. DayMon, Jan 19
- Presidents DayMon, Feb 16
- Memorial DayMon, May 25
- Juneteenth National Independence DayFri, Jun 19
- Independence DayFri, Jul 3
- Labour DayMon, Sep 7
- Columbus DayMon, Oct 12
- Veterans DayWed, Nov 11
- Thanksgiving DayThu, Nov 26
- Christmas DayFri, Dec 25
About these zones
Colombo uses India Standard Time (IST). To call Sri Lanka, dial +94.
Central Time is also known as CST, or CDT. To call United States, dial +1.
Central Time is approximately 8,950 miles north of Colombo.
Quick reference
Full 24-hour conversion table — tap any time to open it in the converter.
| Colombo | CST | Day |
|---|---|---|
| 12:00 am | 1:30 pm | -1 day |
| 1:00 am | 2:30 pm | -1 day |
| 2:00 am | 3:30 pm | -1 day |
| 3:00 am | 4:30 pm | -1 day |
| 4:00 am | 5:30 pm | -1 day |
| 5:00 am | 6:30 pm | -1 day |
| 6:00 am | 7:30 pm | -1 day |
| 7:00 am | 8:30 pm | -1 day |
| 8:00 am | 9:30 pm | -1 day |
| 9:00 am | 10:30 pm | -1 day |
| 10:00 am | 11:30 pm | -1 day |
| 11:00 am | 12:30 am | Same day |
| 12:00 pm | 1:30 am | Same day |
| 1:00 pm | 2:30 am | Same day |
| 2:00 pm | 3:30 am | Same day |
| 3:00 pm | 4:30 am | Same day |
| 4:00 pm | 5:30 am | Same day |
| 5:00 pm | 6:30 am | Same day |
| 6:00 pm | 7:30 am | Same day |
| 7:00 pm | 8:30 am | Same day |
| 8:00 pm | 9:30 am | Same day |
| 9:00 pm | 10:30 am | Same day |
| 10:00 pm | 11:30 am | Same day |
| 11:00 pm | 12:30 pm | Same day |
Daylight saving time
Central Time observes daylight saving time; Colombo does not. The offset between the two zones changes when Central Time transitions: on Sunday, November 1, 2026, clocks fall back from CDT to CST.
See the daylight saving time page for transition dates across every time zone.
Daylight today
- Sunrise
- 5:55 AM
- Sunset
- 6:26 PM
- Day length
- 12h 31m
- Sunrise
- 5:16 AM
- Sunset
- 8:25 PM
- Day length
- 15h 9m
Daylight overlap: 1h — 5:55 AM–6:55 AM in Colombo (7:25 PM–8:25 PM in Central Time). Both locations are in daylight during this window.
Cities in these zones
Cities in Central Time
Browse all cities to see the current local time anywhere.
Airports in these zones
Airports in India Standard Time
- CMB
- RML
Airports in Central Time
- GYY
- MDW
- ORD
- HOU
- IAH
- SAT
- DAL
- DFW
- AUS
- BNA
Related conversions
Common conversions
- What is 9:00 am Colombo in CST?
- 9:00 am Colombo is 10:30 pm CST, the previous day.
- What is 12:00 pm Colombo in CST?
- 12:00 pm Colombo is 1:30 am CST.
- What is 12:30 pm Colombo in CST?
- 12:30 pm Colombo is 2:00 am CST.
- What is 2:00 pm Colombo in CST?
- 2:00 pm Colombo is 3:30 am CST.
- What is 5:00 pm Colombo in CST?
- 5:00 pm Colombo is 6:30 am CST.
- What is 11:30 pm Colombo in CST?
- 11:30 pm Colombo is 1:00 pm CST.