Thailand Trip Planning 2026: When to Go, How to Route It, What It Costs
PEANUTMO Thailand Planning Guide
Thailand is one of the easiest countries in Asia to plan independently, and one of the easiest to plan badly. The two mistakes are going in the wrong month for the region you picked, and trying to combine north and south in a week. Get the timing and the routing right and everything else — transport, food, budget — falls into place.
When to go: it depends which Thailand you mean
Thailand does not have one season. The Gulf coast islands run on a different rhythm from the Andaman coast, and the north is different again. Booking Koh Samui in November because "November is dry season" is a classic and expensive mistake.
| Region | Best months | Avoid | Notes |
|---|---|---|---|
| Bangkok & central | Nov – Feb | Apr – May (hottest) | Cool season is comfortable; April is genuinely punishing heat. |
| North (Chiang Mai, Pai) | Nov – Feb | Mar – Apr (burning season) | Air quality in March and April is poor enough to affect the trip. |
| Andaman (Phuket, Krabi, Phi Phi) | Nov – Apr | May – Oct (monsoon) | Rough seas can cancel boat transfers in low season. |
| Gulf (Samui, Phangan, Tao) | Feb – Sep | Oct – Dec (their rainy season) | Runs opposite to the Andaman coast. This catches people out. |
The practical rule: if you are going November to February, almost anywhere works. Outside that window, pick the coast that matches your dates rather than the dates that match your coast.
Getting there and getting around
- Bangkok has two airports. Suvarnabhumi (BKK) takes most international flights; Don Mueang (DMK) handles most budget carriers. They are an hour apart in traffic — do not book a tight self-transfer between them.
- Domestic flights are cheap and fast. Bangkok to Chiang Mai or Phuket is around 90 minutes and often costs less than the overnight train.
- The overnight train to Chiang Mai is a genuine experience rather than merely transport. Book a second-class sleeper well ahead.
- Islands need ferries or joint bus-boat tickets. Add buffer time; connections slip, especially in rougher months.
- In cities, use ride-hailing apps. Fares are quoted upfront, which removes the meter negotiation entirely.
Routing: do not try to do everything
What to actually do
- Bangkok: Grand Palace and Wat Pho early in the morning, Chatuchak market at the weekend, a river boat rather than a taxi, and street food in Chinatown after dark.
- Chiang Mai: old city temples, an ethical elephant sanctuary (research this carefully), a cooking class, and Doi Suthep at sunset.
- Islands: pick by personality — Koh Tao for diving, Koh Lanta for quiet, Phi Phi for scenery and crowds, Koh Samui for comfort and infrastructure.
- Everywhere: eat at the busy stalls with a queue of locals. It is both the best and the cheapest food in the country.
Budget expectations
| Item | Typical range |
|---|---|
| Street food meal | Very cheap — often less than a coffee at home |
| Mid-range restaurant | Moderate; tourist-area beachfront is several times higher |
| Guesthouse / mid-range hotel | Excellent value outside peak season and outside Phuket |
| Domestic flight | Low if booked ahead, high last-minute in high season |
| Islands vs mainland | Islands are noticeably more expensive for everything, including water |
Two things to sort before you fly
Entry formalities. Thailand has introduced a digital arrival card requirement. Confirm what applies to your nationality and complete it in advance rather than at the airport.
Connectivity. Almost everything above — ride-hailing, ferry bookings, maps, translating a menu, finding the stall with the queue — runs through your phone. Our Thailand eSIM uses the Dtac network with solid coverage across Bangkok, the north and the main islands. Install it at home over Wi-Fi before departure and activate when you land, so you have data from the moment you clear immigration rather than after queueing at an airport SIM counter.
Frequently asked questions
What is the best month to visit Thailand?
November to February works almost everywhere. Outside that, match your destination to the season: the Andaman coast is best November to April, the Gulf islands February to September.
Can I do Chiang Mai and the islands in one week?
Technically yes, but you will spend two of seven days in transit. Bangkok plus one other destination is a far better week.
Should I fly or take the train to Chiang Mai?
Fly if time matters — it is 90 minutes and often cheaper. Take the overnight sleeper if the journey itself appeals; book a second-class berth in advance.
How much data do I need?
Around 500 MB to 1 GB per day covers maps, messaging and ride-hailing. More if you post video or tether a laptop.
Is March a bad time for Chiang Mai?
Yes, generally. Agricultural burning in March and April causes poor air quality across the north, which can be severe enough to spoil outdoor plans.
Do I need to book islands in advance?
In high season, yes — accommodation and ferry seats both. In low season you can usually improvise, but check whether boats are running at all.
Related reading
The digital arrival card, who needs it and when to submit it.
Songkran, Loy Krathong and Bangkok music events, and how to plan around them.
