IST to Colombo
+0hIST
ISTSOURCEColombo
ISTGreen rows indicate typical business hours (9 AM - 5 PM)
IST and IST on the World Map
The map below highlights the IST (India Standard Time) and IST (India Standard Time) timezone regions across the globe.
IST – India Standard Time
UTC+05:30India Standard Time (IST) is the time zone for India and Sri Lanka, 5 hours and 30 minutes ahead of UTC.
- •India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT.
- •India uses a single time zone despite spanning 30° of longitude.
- •IST is one of only a handful of time zones with a 30-minute offset.
- •IST is the most populous single time zone in the world with over 1.4 billion people.
- •The Bombay Stock Exchange (BSE) and National Stock Exchange (NSE) operate on IST.
IST – India Standard Time
UTC+05:30India Standard Time (IST) is the time zone for India and Sri Lanka, 5 hours and 30 minutes ahead of UTC.
- •India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT.
- •India uses a single time zone despite spanning 30° of longitude.
- •IST is one of only a handful of time zones with a 30-minute offset.
- •IST is the most populous single time zone in the world with over 1.4 billion people.
- •The Bombay Stock Exchange (BSE) and National Stock Exchange (NSE) operate on IST.
About Colombo
WikipediaColombo operates on Sri Lanka Time (SLST), UTC+5:30. Sharing India's timezone, Colombo is a key South Asian trade and tourism hub.
Sri Lanka Standard Time (SLST) uses UTC+5:30, same offset as India.
Everything You Need to Know About IST and Colombo Time
IST runs on India Standard Time (IST) at UTC+05:30. Colombo runs on India Standard Time (IST) at UTC+05:30. That puts IST no time difference Colombo — a difference of +0h at the current offsets.
In practice, when it is 9:00 AM in IST it is 9:00 AM in Colombo. Midnight in IST is 12:00 AM in Colombo. Neither zone observes daylight saving time, so the offset between them stays constant all year.
IST to Colombo time conversion table
| IST (IST) | Colombo (IST) | Day |
|---|---|---|
| 12:00 AM | 12:00 AM | same day |
| 6:00 AM | 6:00 AM | same day |
| 7:00 AM | 7:00 AM | same day |
| 8:00 AM | 8:00 AM | same day |
| 9:00 AM | 9:00 AM | same day |
| 12:00 PM | 12:00 PM | same day |
| 3:00 PM | 3:00 PM | same day |
| 5:00 PM | 5:00 PM | same day |
| 6:00 PM | 6:00 PM | same day |
| 9:00 PM | 9:00 PM | same day |
Why people convert IST to Colombo time
- Scheduling a call from IST to Colombo: a 10:00 AM start in IST lands at 10:00 AM in Colombo, so you can confirm the slot without doing the arithmetic yourself.
- Finding shared working hours: both IST and Colombo are inside the 9-to-5 working day between 9:00 AM and 5:00 PM IST time (9:00 AM–5:00 PM IST). That is roughly 8 hours of usable overlap.
- Coordinating a IST-based team with Colombo contacts: quoting times in the other side's local clock — not your own — removes the single biggest source of missed meetings.
- Always state the zone abbreviation, not just the hour. "3:00 PM IST" is unambiguous; "3 PM" across a +0h gap is not.
- Block 9:00 AM–5:00 PM IST as the recurring meeting window if you work primarily from IST and need Colombo colleagues present.
About IST (India Standard Time)
India Standard Time (IST) is the time observed throughout India and Sri Lanka. It is based on the 82.5°E meridian, passing through Mirzapur in Uttar Pradesh. India uses a single time zone despite spanning roughly 30° of longitude, which has been debated. IST does not observe daylight saving time. India is the world's most populous country, making IST one of the most-used time zones globally. The IT outsourcing industry and call centers operate primarily on IST, making the EST-to-IST conversion one of the most searched timezone conversions.
About IST (India Standard Time)
India Standard Time (IST) is the time observed throughout India and Sri Lanka. It is based on the 82.5°E meridian, passing through Mirzapur in Uttar Pradesh. India uses a single time zone despite spanning roughly 30° of longitude, which has been debated. IST does not observe daylight saving time. India is the world's most populous country, making IST one of the most-used time zones globally. The IT outsourcing industry and call centers operate primarily on IST, making the EST-to-IST conversion one of the most searched timezone conversions.
Best time to call between IST and Colombo
Both IST and Colombo sit inside the 9 AM – 5 PM working day between 9:00 AM–5:00 PM IST, which is 9:00 AM–5:00 PM IST. That gives roughly 8 hours of shared time — the safest window for a live call or meeting.
Business hours overlap
IST and Colombo share 8 hours of working-hours overlap (9:00 AM–5:00 PM IST), so scheduling a live meeting is straightforward.
IST is no time difference Colombo (IST UTC+05:30 → IST UTC+05:30). The shared working window is 9:00 AM–5:00 PM IST. Remember to re-check around daylight-saving transitions.
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 IST and Colombo?
IST (IST, UTC+05:30) is no time difference Colombo (IST, UTC+05:30). The gap is currently +0h.
How do I convert IST time to Colombo time?
Add +0h to IST local time. For example, 9:00 AM in IST is 9:00 AM in Colombo.
What time is it in Colombo right now?
Colombo uses IST at UTC+05:30. Use the live converter at the top of this page — it updates in real time and already accounts for the +0h offset from IST.
What is the best time to call Colombo from IST?
Call between 9:00 AM and 5:00 PM IST — that maps to 9:00 AM–5:00 PM IST and keeps both parties inside the working day.
Which is ahead, IST or Colombo?
IST and Colombo are currently on the same clock.
Do IST and Colombo use different time zones?
IST uses IST at UTC+05:30, while Colombo (Sri Lanka) uses IST at UTC+05:30. The IANA identifiers are Asia/Kolkata and Asia/Colombo.
Does daylight saving time affect the IST–Colombo difference?
Neither zone observes daylight saving time, so the +0h offset between IST and Colombo is fixed all year.
Which other cities share IST's time zone?
IST also covers Mumbai, Delhi, Bangalore, Kolkata, Chennai, Hyderabad, Pune, Ahmedabad and 4 more.
Which countries use IST, IST's zone?
IST is used in India, Sri Lanka.
What is the time difference between IST and Colombo?
Colombo is +0h from IST.
What timezone is IST in?
IST operates on its local timezone.
What timezone is Colombo in?
Colombo operates on Sri Lanka Time (SLST), UTC+5:30. Sharing India's timezone, Colombo is a key South Asian trade and tourism hub.
What are the business hours in Colombo?
Standard business hours in Colombo are 9:00 AM - 5:00 PM IST.
Which countries use IST (India Standard Time)?
IST is used in India, Sri Lanka.
Does IST observe daylight saving time?
No, IST does not observe daylight saving time and remains at UTC+05:30 year-round.
What are some interesting facts about IST?
India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT. India uses a single time zone despite spanning 30° of longitude.
Which cities are in the IST timezone?
Major cities in the IST timezone include Mumbai, Delhi, Bangalore, Kolkata, Chennai, Hyderabad, Pune, Ahmedabad.
What is the UTC offset for IST?
India Standard Time (IST) is at UTC+05:30.
What should I know about the IST timezone?
India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT. India uses a single time zone despite spanning 30° of longitude.
When is it midnight in IST, what time is it in Colombo?
When it is 12:00 AM (midnight) in IST (IST), it is +0h later in Colombo (IST).
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