Almost every Thailand itinerary that lands on my desk has the same shape: three nights in Bangkok, two in Chiang Mai, four on an island, home. It works. It is also the version of Thailand you'd design if you'd never been, and it misses the thing that makes the country worth the flight — that it is three genuinely different places stacked on top of each other.
Bangkok, longer than you want
Start in Bangkok and give it more than you want to. Three nights minimum, four if you can stand the heat. The first day is a write-off to jet lag, the second is temples and the river, and the third is when the city stops being overwhelming and starts being legible. Stay riverside if it's your first time — the boat is the only sane way to move through the city — and eat where the plastic stools are. The best meal of your trip will cost about two dollars and you will not be able to find the place again.
Then go north
Then go north. Chiang Mai is an hour and fifteen in the air and a different country: cooler, slower, hemmed in by hills, and still built around a moat. Two nights there is enough to see the old city and eat khao soi properly. But the reason to come north is what's past it — the drive out to Mae Hong Son, the villages around Pai, the temples up at Chiang Rai. Give the north four nights and rent a driver rather than a scooter, whatever the internet tells you.
Pick the right coast
The islands are where people get it wrong, and it's a matter of which coast. Thailand's two coasts run on opposite monsoons. The Andaman side — Phuket, Krabi, Koh Lanta — is at its best from November through April. The Gulf side — Koh Samui, Koh Phangan, Koh Tao — runs roughly February through September and gets hammered in November, which is peak season everywhere else. Booking a Gulf island for a November honeymoon is the single most common Thailand mistake, and it is entirely avoidable.
For a first trip we usually send people to the Andaman side but not to Phuket itself. Koh Yao Noi sits in the middle of Phang Nga Bay, twenty minutes by boat from the mainland, and has the same limestone-karst view everyone flies to Thailand for without the wall of resorts. If you want quieter still, Koh Kood is four hours from Bangkok and feels like the country did twenty years ago.
When to go
On timing: November to February is the dry, cool window and the whole country knows it, so book seven to nine months out. March through May is genuinely hot — forty degrees in Bangkok is not unusual. Songkran, the water festival, falls on 13–15 April; it is either the best thing you will ever do or a logistical nightmare, depending entirely on whether you planned to be in it.
The flights that break itineraries
A word on the internal flights, because they're the part that quietly breaks Thailand itineraries. The domestic network is cheap, frequent, and run by several carriers that do not share baggage agreements or reschedule you onto each other when something slips. Bangkok also has two airports, and a same-day connection that moves you between them is a bad idea with luggage. We build in buffer nights at the transition points rather than trusting a tight connection, and we book the island boats separately — most of them don't appear on any booking site at all, and the last departure is usually earlier than you'd guess.
How long to give it
Sixteen nights covers all three parts without a single rushed morning. Twelve works if you cut the north to two nights. Ten means picking two of the three, and we'd cut the islands before we cut Bangkok — a decision nobody likes hearing and everybody agrees with afterwards.
