Best time to visit Thailand from the UK: weather by month, what to see and safety

It depends on the coast you want. The Tourism Authority of Thailand's newsroom describes November to February as the cool season, at 18°C to 28°C, and in the Thai Meteorological Department's figures Bangkok's driest month is December, with 11.6 mm of rain. On the beaches the windows differ: Thailand.go.th gives November to April for the Andaman Sea coast and April to October for the Gulf of Thailand coast, and the department's Ko Samui station records its heaviest rain in November, at 444.6 mm.

We read the department's 1991 to 2020 climate normals for four stations, the Tourism Authority of Thailand newsroom's guide to the seasons and Thailand.go.th's beach guide for the seasons and coasts, and GOV.UK's foreign travel advice for Thailand for safety and entry rules, all on 9 November 2026. GOV.UK shows that its Thailand advice was last updated on 12 October 2026, when it revised the visa requirements information, and it was still current on 9 November 2026. The newsroom articles carry their own dates, given where we use them, and the safety pages of GOV.UK show no update date of their own, so check the main advice page for changes before you fly.

Thailand is long, so one city cannot stand for the country. The table gives the Thai Meteorological Department's averages for 1991 to 2020 at four stations: Bangkok, Chiang Mai in the north, Phuket and Ko Samui in the south. Each cell shows the mean daily maximum and minimum in degrees Celsius, then the month's rainfall in millimetres.

In Bangkok the wettest month is September, with 335.9 mm, the driest is December, with 11.6 mm, and April is the hottest, with a mean maximum of 35.7°C. Chiang Mai reaches 36.7°C in April and is the cool one in the table, with a January mean minimum of 15.7°C; its wettest month is August, at 223.3 mm. Phuket is wettest in September, at 350.4 mm, and driest in February, at 24.0 mm. Ko Samui follows a different calendar: its wettest month is November, at 444.6 mm, and its driest is February, at 64.3 mm.

The figures come from the department's own report, which you can open as the Climatological Data of Thailand for 1991 to 2020.

There is no single month that suits every region, but there is a clear pattern. The table sets the three seasons the Tourism Authority of Thailand's newsroom describes beside what the department's figures and GOV.UK say for the same months.

The Andaman Sea side from November to April, and the Gulf of Thailand side from April to October, according to Thailand.go.th, whose beach guide was last updated on 10 June 2025. It says of the Andaman coast that “The best time to visit is November to April, when the weather is great, the water is clear, and the sea is calm,” and of the Gulf coast that “April to October is ideal for this region, with good weather and perfect conditions for relaxing by the shore.” The table sets the rainfall at Phuket and Ko Samui beside those windows.

At Ko Samui every month from April to September has under 134 mm of rain in the department's table, but October, which sits inside the Thailand.go.th window, is already the second wettest month there, at 294.9 mm. The newsroom of the Tourism Authority of Thailand, in an article of 17 November 2020 on the cooler months, lists “Popular destinations like Phuket, Krabi and the Phi Phi Islands” for the November to February period. Whichever island you choose, check the newsroom's guide to the cooler months and the department's forecast for the week you fly.

The Tourism Authority of Thailand's newsroom names places by season and festival rather than by month, so the table gathers what it names, with the dates it gave. If you travel this month, the Loi Krathong window of 15 to 29 November 2026 is the one to check.

The newsroom's Loi Krathong 2026 article gives the full programme. For April, the newsroom said in March 2021 that Songkran is officially observed as a three-day national holiday from 13 to 15 April; confirm the dates and events for 2027 nearer the time.

GOV.UK's safety and security page for Thailand sets out the natural hazards in one place, and it is the page to read once you have chosen your dates. It tells you to monitor the Thai Meteorological Department for weather warnings.

The FCDO advises against all but essential travel to parts of Thailand: the areas near the borders with Cambodia and Malaysia in the table. The advice covers parts of the country, not all of it, and GOV.UK also warns that terrorists are likely to try to carry out attacks in Thailand.

Details of each area are in GOV.UK's regional risks page. For help in an emergency, GOV.UK's getting help page lists 191 for the police, 1669 for an ambulance, 199 for fire and 1155 for the tourist police.

Several rules differ sharply from the UK, and GOV.UK says some have no exception for tourists. The table picks out the ones it stresses.

Our Thailand visa guide for British passport holders sets out the entry rules in full.

GOV.UK says Thailand has a high number of road traffic accidents, particularly with motorcycles. Its advice on riding and driving is short and specific.

• Helmets
  By law, you must wear a helmet when riding a motorcycle.
• Hired bikes
  Motorcycles and scooters for hire in tourist areas are often unregistered and cannot be used legally on a public road.
• Driving permit
  You cannot buy an international driving permit outside the UK, so get one before you travel.

Our guide to the international driving permit explains which one you need and how to get it.

GOV.UK says that from 15 September 2026 you can stay for up to 30 days for tourism only, that your passport must have an expiry date at least 6 months after the date you arrive and at least 1 blank page, and that travellers can register for an arrival card within 3 days before they arrive. Our Thailand visa guide covers the entry rules in more detail, and our arrival card guide explains the online form. The rules are read from GOV.UK's entry requirements page, which GOV.UK updated on 12 October 2026 and which was current on 9 November 2026.

Work from the date of your trip: the season sets what you pack and where you stay, and the entry and safety rules do not change with it.

• Your coast and month
  Andaman side from November to April, Gulf side from April to October, according to Thailand.go.th, and the rainfall table above.
• Your forecast
  GOV.UK tells you to monitor the Thai Meteorological Department for weather warnings.
• Your passport
  Expiry date at least 6 months after you arrive, and 1 blank page.
• Your arrival card
  Register within 3 days before you arrive.
• Your health
  GOV.UK's health page says to check vaccine guidance at least 8 weeks before your trip.
• Your areas
  Check the FCDO's advice on the Cambodian and Malaysian borders before you plan a route.
• Your numbers
  191 for the police, 1669 for an ambulance, 199 for fire, 1155 for the tourist police.

Our travel vaccinations guide explains where to get jabs in the UK, the GOV.UK health page lists the risks for Thailand, our jet lag guide helps with the long flight, and the holiday packing list puts documents first. More general advice is in our travel tips for UK travellers.

• When is the best time to visit Thailand?

  The Tourism Authority of Thailand’s newsroom describes November to February as the cool season, at 18°C to 28°C. For beaches, Thailand.go.th gives November to April for the Andaman Sea coast and April to October for the Gulf of Thailand coast.

• When is the rainy season in Thailand?

  The Tourism Authority of Thailand’s newsroom gives May to October. In the Thai Meteorological Department’s figures Bangkok is wettest in September, with 335.9 mm, and Ko Samui is wettest in November, with 444.6 mm.

• What is the weather like in Thailand in December?

  Bangkok averages 32.3 / 23.2°C and 11.6 mm of rain, Chiang Mai 29.2 / 16.9°C and 14.1 mm, Phuket 32.1 / 25.0°C and 82.0 mm and Ko Samui 29.3 / 24.0°C and 263.1 mm, from the department’s 1991 to 2020 averages.

• Which is the hottest month in Thailand?

  April, at the two cities in the department’s table: the mean daily maximum is 35.7°C in Bangkok and 36.7°C in Chiang Mai.

• Which coast is better for a beach holiday?

  Thailand.go.th gives November to April for the Andaman Sea coast and April to October for the Gulf of Thailand coast. At Ko Samui the department’s rainfall for October is already 294.9 mm.

• Is Thailand safe for British tourists?

  The FCDO advises against all but essential travel to parts of Thailand, near the borders with Cambodia and Malaysia. It also warns that terrorists are likely to try to carry out attacks, and it stresses road safety and local laws.

• Do British citizens need a visa for Thailand?

  GOV.UK says that from 15 September 2026 you can stay for up to 30 days for tourism only. Our Thailand visa guide has the detail.

• What is the emergency number in Thailand?

  GOV.UK’s getting help page lists 191 for the police, 1669 for an ambulance, 199 for fire and 1155 for the tourist police.

• Can I take a vape to Thailand?

  No. GOV.UK says it is illegal to possess or use any vape, e-cigarette, pod, e-liquid or heat-not-burn device in Thailand, with no exceptions for tourists or for personal use.

• Do I need an international driving permit in Thailand?

  GOV.UK says you cannot buy an international driving permit outside the UK, so get one before you travel. It adds that you must wear a helmet by law when riding a motorcycle.