The best time to send cold email in Southeast Asia is the prospect's local weekday morning, about 8:30 to 10:30, on a working day that isn't next to a long holiday. The difficulty is that the region has three time zones, two weekend patterns and very different holiday calendars. In early 2027, Tet, Chinese New Year and the expected start of Ramadan all fall within about three days of each other.
This guide covers Vietnam, Singapore, Malaysia, Indonesia, Thailand and the Philippines. For each country it gives the time zone, the working week, our suggested send windows and the 2027 dates to keep clear.
Key Takeaways
Send in the prospect's local time. Vietnam, Thailand and western Indonesia are on UTC+7. Singapore, Malaysia, the Philippines and central Indonesia are on UTC+8. Eastern Indonesia is on UTC+9.
In Malaysia, Kedah, Kelantan and Terengganu take Friday and Saturday as their weekend. Johor went back to Saturday–Sunday in January 2025.
4–10 February 2027 is a dead zone for much of the region: Tet, Chinese New Year and the expected start of Ramadan (around 8 February).
Other 2027 breaks: Hari Raya Aidilfitri / Lebaran (around 10–11 March), Holy Week in the Philippines (25–27 March) and Songkran in Thailand (13–15 April).
General send-time studies mostly use US data. Use them as a starting point, then test against your own replies.
Why doesn't one global send time work for Southeast Asia?
Time zones. A one-hour gap between Jakarta and Manila rarely hurts. The real problem is sending at the end of your own day, or from Europe or the US. Those emails arrive overnight and are buried by everything that lands before the prospect starts work.
Weekends. Most of the region rests on Saturday and Sunday, but three Malaysian states rest on Friday and Saturday and work on Sunday. A Friday email to a company in Kota Bharu reaches someone on their weekend.
Holidays. Lunar New Year, Ramadan and Eid, Holy Week and Songkran close or slow different countries at different times. Emails sent into a holiday then compete with the backlog on the first day back.
What is the best time to send cold email in Vietnam?
Time zone: UTC+7, no daylight saving.
Working week: Monday to Friday in most offices. The Labour Code allows up to 48 normal working hours a week, so some private companies also work Saturdays. Don't rely on a Saturday read.
Best windows: Tuesday to Thursday, 8:30–10:30 local time. Early afternoon, after lunch, is a second option.
2027 dates to avoid:
Tet: Lunar New Year is Saturday 6 February. The public sector is off from Thursday 4 to Wednesday 10 February. Private firms choose their own five statutory days around New Year's Eve (Friday 5 February), so treat that whole week as closed.
Hung Kings Commemoration: Friday 16 April.
30 April and 1 May: Friday and Saturday. Staff on a Saturday–Sunday week get Monday 3 May off in lieu.
National Day: Thursday 2 September plus one adjacent day. The public sector is off from 2 to 5 September.
Vietnam Culture Day: Wednesday 24 November, a paid day off since 2026.
What is the best time to send cold email in Singapore?
Time zone: UTC+8.
Working week: Monday to Friday.
Best windows: Tuesday to Thursday, 8:30–10:00 local time. Many regional managers are based here. If your prospect covers Vietnam or Indonesia, their workload follows those holidays too.
2027 dates to avoid (Ministry of Manpower): 1 January; Chinese New Year on 6–7 February, with Monday 8 February off; Hari Raya Puasa on Wednesday 10 March; Good Friday on 26 March; Hari Raya Haji on Monday 17 May; Vesak Day on Thursday 20 May; National Day on Monday 9 August; Deepavali on Thursday 28 October; Christmas on Saturday 25 December.
What is the best time to send cold email in Malaysia?
Time zone: UTC+8.
Working week: Saturday–Sunday in most states. Kedah, Kelantan and Terengganu rest on Friday and Saturday and work on Sunday. Johor returned to Saturday–Sunday on 1 January 2025.
Best windows: Tuesday to Thursday, 9:00–11:00 local time. Monday to Thursday is safe in every state. Friday midday is set aside for prayers (Johor gives a two-hour break), so any Friday send should go early in the morning.
2027 dates to avoid (Prime Minister's Department list, as circulated by FMM):
Chinese New Year: 6–7 February.
Awal Ramadan: Monday 8 February, a state holiday in Johor and Kedah (subject to moon sighting).
Hari Raya Aidilfitri: Wednesday 10 and Thursday 11 March (subject to change). Many people stretch it into a full week.
Hari Raya Haji: Monday 17 May. Wesak: Thursday 20 May. Agong's Birthday: Monday 7 June.
National Day: Tuesday 31 August. Malaysia Day: Thursday 16 September. Deepavali: Thursday 28 October (except Sarawak). Christmas: 25 December.
State holidays: If your list is concentrated in one state, check that state's own days, such as rulers' birthdays.
What is the best time to send cold email in Indonesia?
Time zones: three, with no daylight saving. WIB (UTC+7): Sumatra, Java and West and Central Kalimantan, including Jakarta and Surabaya. WITA (UTC+8): Bali, Sulawesi and East and South Kalimantan. WIT (UTC+9): Maluku and Papua. A company in Makassar is an hour ahead of Jakarta.
Working week: Monday to Friday in most offices. Friday mornings work better than Friday afternoons.
Best windows: Tuesday to Thursday, 9:00–11:00 local time. During Ramadan, send earlier and keep emails short.
2027 dates to avoid (joint ministerial decree, 15 September 2026):
Isra Mikraj: Tuesday 5 January.
Imlek: Saturday 6 February, with cuti bersama (collective leave) on Friday 5 February.
Ramadan: expected to start around 8 February.
Nyepi: Monday 8 March.
Idulfitri (Lebaran): 10–11 March, with cuti bersama on 9, 12 and 15 March. The weeks either side are slow because of mudik, the travel home.
Easter: Good Friday on 26 March, with cuti bersama on 25 March. Ascension Day is Thursday 6 May and Pancasila Day is Tuesday 1 June.
17–20 May: Iduladha, Waisak and two cuti bersama days, so most of that week is lost.
Independence Day: Tuesday 17 August. Christmas: 25 December, with cuti bersama on 24 December.
Cuti bersama is optional for private companies, but treat those days as low-response days anyway.
What is the best time to send cold email in Thailand?
Time zone: UTC+7.
Working week: Monday to Friday for most B2B offices.
Best windows: Tuesday to Thursday, 9:00–11:00 local time. Keep the email short and plain. If you write good Thai, test a Thai version.
2027 dates to avoid (Bank of Thailand 2027 holiday calendar; the cabinet can still add days):
New Year: 1 January, and New Year's Eve on 31 December.
Makha Bucha: Monday 22 February off in lieu.
Chakri Day: Tuesday 6 April.
Songkran: Tuesday 13 to Thursday 15 April. In past years the cabinet has added extra Songkran days, so expect the whole week to be quiet.
May: Monday 3 May (Labour Day in lieu, private sector), Coronation Day on 4 May and Visakha Bucha on 20 May.
Single days: 3 June, 19 July, 28 July, 12 August, 13 October, 25 October, 6 December and 10 December.
What is the best time to send cold email in the Philippines?
Time zone: UTC+8.
Working week: Monday to Friday in most offices. BPO teams often work shifts that follow their clients' hours, so a manager at a Manila contact centre serving US clients may be active late in the day.
Best windows: Tuesday to Thursday, 9:00–11:00 local time for office roles.
2027 dates to avoid (Proclamation No. 1427):
Holy Week: Maundy Thursday 25 March, Good Friday 26 March and Black Saturday 27 March. Avoid the whole week of 22 March.
Other days: Araw ng Kagitingan on Friday 9 April, National Heroes Day on Monday 30 August, and All Saints' and All Souls' Days on 1–2 November.
Eid'l Fitr and Eid'l Adha: to be set by separate proclamations.
December: 8, 24, 25, 30 and 31 December are all holidays or non-working days. Treat 20 December to 4 January as a dead zone.
What is the February 2027 problem?
In 2027, the region's biggest holidays cluster together:
4–10 February: Tet break in Vietnam.
5–8 February: Chinese New Year in Singapore, Malaysia and Indonesia, plus 6 February in the Philippines.
Around 8 February: Ramadan is expected to begin, bringing a month of shorter office days in Malaysia and Indonesia.
The last week of January is weak too, as people clear their desks. Then Hari Raya and Lebaran arrive around 10 March, a second dip only four weeks later.
What to do before mid-January 2027:
Start Q1 outreach early. Send first emails and the first follow-up by about 22 January.
Schedule nothing for 1–12 February in Vietnam, Singapore, Malaysia or Indonesia. From Monday 15 February, send a short new email rather than "following up from before Tet".
Plan a second push for 15 February to 5 March, then pause Malaysia and Indonesia from about 8 to 16 March.
Use early February for Thailand and the Philippines, which are mostly unaffected.
How do you schedule a multi-country cold email campaign?
Split your list by country, and by time zone within Indonesia.
Schedule each list in the prospect's local time, aiming for 8:30–10:30.
Set sending days per market. Monday to Thursday is the safe default. Use Sunday to Thursday only for Kedah, Kelantan and Terengganu.
Block holiday windows in advance, including the day before and the day after each long break.
Plan follow-ups around holidays, not through them. Our sales follow-up email guide covers spacing. Just check that no step lands on Tet or Lebaran.
Ramp up after breaks. Don't send a huge batch into full inboxes on the first day back. Our cold email deliverability guide explains why volume spikes hurt.
Test, then trust your own data. Compare two time slots on similar segments over a few weeks and judge by replies. A clear subject line and a relevant message matter more than the exact hour.
How does Saella help?
Saella is a B2B prospecting and AI cold email tool for Southeast Asia. For timing, you can:
Pick sending days for each campaign, for example leaving out Fridays for a Friday-weekend state or skipping a holiday week.
Filter companies by country, so each market gets its own list and schedule.
Set follow-ups to wait a number of days and go only to people who opened.
Review and approve every AI-written email before it goes out. Our B2B cold email templates give you a starting point.
Frequently Asked Questions
What is the best day to send a cold email in Southeast Asia?
Tuesday to Thursday is the safest choice in every market. Avoid Fridays for Kedah, Kelantan and Terengganu, and avoid the day before or after any long holiday.
What time should I send cold emails to Southeast Asia?
Send in the prospect's local morning, about 8:30 to 10:30. Use UTC+7 for Vietnam, Thailand and western Indonesia, UTC+8 for Singapore, Malaysia, the Philippines and central Indonesia, and UTC+9 for eastern Indonesia.
Should I send cold emails during Ramadan?
Yes, but send earlier in the day and keep messages short. Pause for the week around Hari Raya Aidilfitri / Lebaran, expected around 10–11 March 2027.
Are general send-time studies useful for Southeast Asia?
Only as a starting point. Most published studies use US and European sender data. Test two time slots on your own lists and judge by replies.
Plan Your 2027 Outreach With Saella
Build lists by country and set sending days around the 2027 holidays with Saella at www.saella.ai.
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