3 Weeks In Thailand – Detailed Itinerary + Unbelievable Trip Costs

Last Updated on 7 November 2022

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So you’re wondering how to spend 3 weeks in Thailand?

The Land of Smiles… Of sandy beaches, chaotic cities, intricate temples, dramatic karst scenery, elephant sanctuaries, dense green jungles, and mischievous monkeys… Of colourful tuk-tuks, long-tail boats, and rickety overnight trains… Of rich history, vibrant culture, and mouth-watering food…. And where a trip is an essential part of any bucket list for Southeast Asia! So if you need a ridiculously detailed itinerary for 3 weeks in Thailand to help you experience a country that is considered a mecca for backpackers and travellers from all across the world, then you have come to the right place!

Elephants bathing in a river in Chiang Mai - 3 weeks in Thailand
Elephant Nature Park, Chiang Mai

3 weeks in Thailand is the perfect amount of time to get a good taste of what this stunning country is all about! And being an affordable destination it can be done on a budget (psst… you can see my unbelievable travel costs for this exact trip at the end of this itinerary)! Like many, Thailand was the first place I went backpacking in Southeast Asia. And since doing this exact 3 week itinerary for Thailand, I’ve been on various trips around the continent, such as to Bali, Cambodia and Hong Kong, to Singapore, Malaysia and Bali, to Beijing and Hong Kong, and to Vietnam!

Erawan Waterfalls in Thailand
One of the falls at Erawan Waterfalls outside of Bangkok

I use the term backpacking very loosely. And I want to clarify what I mean by backpacking, so you know what you can expect from this itinerary… When you think of backpacking Thailand, you might think of hostels, street food and travelling with no set plan. But that’s not my type of backpacking. For me it meant that yes, I had a backpack in which I carried my belongings to travel through Thailand, I used some public transport, and I travelled Thailand on a budget. But I also travelled by aeroplane, stayed in hotels, mostly ate in restaurants, and the trip was pre-planned down to the finest detail. I guess you could say that I was a flashpacker. Travel politics aside, I present to you the perfect 3 weeks in Thailand!

Itinerary overview for 3 weeks in Thailand

Day 1: International travel from home country to Thailand
Day 2-5: Bangkok including 2 day trips out of the city
Day 6-8: The ancient capital of Ayutthaya
Day 9-13: Chiang Mai including 2 day trips out of the city
Day 14-16: Ao Nang, Krabi
Day 17-20: Phuket including 1 day trip away from the island
Day 21-22: Bangkok (prior to return flight back to home country)
Day 23: International travel from Thailand to home country

This 3 week itinerary for Thailand is actually 23 days long (depending on how you look at it)… It gives you 21 full days in Thailand, and allows for 1 day of international travel either side of your trip. This is because it is likely that you will lose a full day either side of this itinerary depending on your departure country, and no one wants to be shortchanged of time in Thailand, do they? If you need to shorten this trip to 3 weeks including international travel, then make cuts and amendments as you need. After all it’s only a guide for how to spend 3 weeks in Thailand!

A monkey at in a tree at Erawan Waterfalls in Thailand
A monkey at Erawan Waterfalls in Thailand

It’s likely that your international flights are going to arrive into and depart from Bangkok. You may arrive into Phuket, and if this is the case then you should start this itinerary at Day 17. If your Thailand itinerary forms part of a larger trip, you can often get cheap flights to neighbouring countries such as Vietnam, Malaysia and Indonesia from Thailand. Your largest expense is probably going to be the international flights to/from Thailand, and if it’s not you might want to question why! But like a lot of Southeast Asian countries, once you are there it is super affordable!

Know before you go

Always check the entry requirements for the country you are visiting to see if you will need a Visa to enter, and that you have enough validity left on your passport.

Always have a good level of travel insurance for every international trip. This is a non-negotiable part of any trip abroad, as the unexpected can happen.

What is the currency in Thailand?

The currency in Thailand is the Thai Baht.

When is the best time to visit Thailand?

Thailand is a year-round destination with a varying climate throughout the country. But depending on your personal preference there are some months which you may find better for travelling Thailand.

NOVEMBER-APRIL (dry season): If you want dry and warm weather, November-April is the best time to visit Thailand. During these months, temperatures can reach highs of up to 36°C and the days can see around 9 hours of Southeast Asian sunshine. November-February is classed as high season in Thailand.

MARCH-OCTOBER (rainy season): Generally, the rainy season in Thailand spans from March-October. This is with the exception of the east coast of southern Thailand which spans from September-December. But don’t let that deter you from visiting Thailand during these months! I spent 3 weeks in Thailand doing this exact itinerary in July, and only experienced one short lived torrential downpour during that time. The heavy rainfall is usually over within a few hours (just pack an umbrella)!

Elephant Nature Park in Thailand
Elephant Nature Park in Chiang Mai

International departure: Day 1

Day 1: Allow at least 1 full day to be lost for international travel to Southeast Asia if you are travelling from outside the region.

Bangkok: Day 2-5

You might think that 4 days in Bangkok is way to much time to spend in a city that is full of chaos, and this would be down to your own unique preference. Personally, I wanted that amount of time to recuperate from the jet lag, acclimatise to Thailand, do some day trips out of the city, and see the sights of Bangkok. But you could certainly cut this down to 3 days if you need to shorten this trip, or spend more time elsewhere if preferred.

The Grand Palace, Bangkok
The Grand Palace, Bangkok

I strongly disliked Bangkok when I first arrived, and if this happens to you, I’d encourage you to persevere with it! This was probably because I was tired, was delayed in arriving due to a plane collision (true story), and when I got to my Khao San Road hotel they had given away my reservation because of said lateness! Fast forward to the next morning, after (some) sleep in a hotel that I don’t even know the name of, accommodation issues rectified, and a stomach full of food, I slowly befriended Bangkok! Be prepared for some pungent smells, stifling humidity, relentless noise of horns, and utter chaos. (I know I’m not selling it, but you’ve got to spend a few days in Bangkok because it is a fabulous place to experience with some wonderful things to see!)

Tip: Before you visit, you need to get acquainted with the best travel tips for Thailand so you’ve got all the practical travel advice you need and can try to avoid any misfortunes!

Damnoen Saduak floating market - 3 weeks in Thailand
Damnoen Saduak Floating Market outside of Bangkok

Day 2: From Bangkok Suvarnabhumi Airport, board the Bangkok Airport Rail Link (ARL) into the city centre. From Phaya Thai (BTS) station, take a taxi to your central hotel (insist the driver uses the meter) or walk if you can. Settle in after your long flight and familiarise yourself with your surroundings. Perhaps do something relaxing, like go on a long-tail boat tour of the khlongs (Thai canals) that are situated off of the Chao Phraya River to see the stilted homes, before heading to dinner.

Note: The hotel I stayed in during my stint in Bangkok seems to have vanished off the face of the earth, but there are an abundance of other insane hotels for Bangkok at Booking.com you can check out.

Day 3: Wake up early and spend day 3 of your three weeks in Thailand experiencing some of the best things to do in Bangkok. Visit some beautifully ornate temples like the Grand Palace, Wat Pho and Wat Arun. For dinner, eat the tastiest Massaman Curry at Ranee’s Restaurant. If you’re feeling brave and fancy some craziness, wander around to the notorious Khao San Road for a Chang (Thai beer). Or, for something tamer, head to a chic rooftop bar to enjoy the Bangkok skyline illuminated at night!

Tip: Pack a sarong and some capped t-shirts because the majority of the temples in Thailand require you to cover your legs and shoulders as part of their dress code (the Grand Palace is particularly strict)!

Erawan Falls in Thailand
One of the falls at Erawan Waterfalls
The Bridge over the River Kwai, Thailand
The Bridge on the River Kwai

Day 4: Today, take a day trip out of Bangkok to the unique Damnoen Saduak Floating Market to see items such as fruit and conical hats stacked up precariously on boats!

Day 5: Go on a combo day trip to Erawan Waterfalls and Kanchanaburi where the historic Death Railway Bridge is located. Wear decent footwear to Erawan Waterfalls – it is quite a hike up through the various levels and can be uneven and slippery. And watch out for the monkeys that live there as they like to indefinitely borrow items that belong to humans!

Tip: You can book day trips from Bangkok before you visit Thailand, or in a local tour agency shop in the city. Booking them before you go will allow you to check out the reviews and reputation of the company.

Ayutthaya: Day 6-8

Ayutthaya is the ancient capital of Siam where ruins of terracotta coloured temples are plentiful and monitor lizards roam the lake-filled parks. Destroyed by the Burmese army in 1767 and now a designated UNESCO World Heritage Site, Ayutthaya is a modern city intertwined with a mysterious past. For a glimpse into its rich history, it is certainly worthy of a few days of your 3 weeks in Thailand. What’s more, it’s super easy and cheap to reach from Bangkok by train, so you’ve got no reason not to include it!

The train from Bangkok to Ayutthaya, Thailand
The train from Bangkok to Ayutthaya

Day 6: Jump on an early train from Bangkok to Ayutthaya (note: the train can be a slow option, but 3rd class is unbelievably cheap, you will avoid traffic jams and see the countryside). When you arrive, settle in and get your bearings. Grab a map of Ayutthaya and plan out which temples within the river boundaries you’d like to visit tomorrow. Scoff Pad Thai and tempura vegetables for dinner, and try to avoid a travel mishap of getting chased by wild dogs.

Note: Unfortunately the hotel I stayed at has now closed down (which is a real shame because it was quite the catch). But fear not, there are a whole host of other hotels for Ayutthaya here.

The ancient city of Ayutthaya in Thailand
Cycling around the ancient city of Ayutthaya in Thailand

Day 7: Rise and shine early, and fuel your body with a nourishing breakfast because day 7 of your Thailand 3 week itinerary is going to be an active one! Spend one whole day sightseeing in Ayutthaya, enjoying the abundance of temple ruins that lie within the river boundaries by bicycle. Make sure you take sun cream, plenty of water, and a hat, and wear decent footwear too! In between the cycling, stop opposite Wat Maha That at the budget-friendly Coffee Old City for lunch.

Tip: There are numerous huts and shops around Ayutthaya where you can rent a bicycle very cheaply for the day. Just do some basic safety checks before you head off, like checking the brakes and making sure everything looks visually ok! Don’t put your valuables in the basket at the front. And make sure you always lock the bike up if unattended.

Wat Chaiwatthanaram in Ayutthaya, Thailand
Wat Chai Watthanaram, Ayutthaya

Day 8: Hire a tuk-tuk driver for a few hours to take you to some of the temples in Ayutthaya which are outside of the river boundaries, such as Wat Yai Chaya Mongkhon. There are various drivers who will offer this service (it’s often advertised on their tuk-tuk), but just make sure you haggle for the price! After something tasty pop to a 7-Eleven to grab water and snacks for the overnight train journey tonight. Then freshen up, collect your luggage, and go to Ayutthaya train station to board your overnight train to Chiang Mai.

Tip: It’s likely you’ll need to check out of your hotel mid-morning on day 8. So why not book a cheap room in one of the hotels opposite the train station to use for luggage storage and showering? I booked one online for this reason whilst I was in Ayutthaya and found a basic double room for just £6.00 for 2 people (~$8.50). This was the overnight price, but I left on the evening of day 8 (yes, Thailand really is that cheap)!

Chiang Mai: Day 9-13

Despite being the largest city in northern Thailand, Chiang Mai has a beautifully chilled vibe. Surrounded by a moat and old city walls, and with a backdrop of jungle-covered mountainous terrain, it is dotted with countless temples and is home to a large night market. This charming city is an unmissable part of any Thailand itinerary for 3 weeks and is a prime location to base yourself to explore the region. From Chiang Mai you can do various day trips and adventurous activities. To be honest, the city is worthy of much more than 5 days (but we are on time limits people, and there’s always next time)!

Wat Chiang Man in Chiang Mai, Thailand
Wat Chiang Man in Chiang Mai

Day 9: Arrive into Chiang Mai train station (probably sleep deprived, but you’ve got to travel by overnight train in Thailand because it’s the quintessential Southeast Asian experience) on the morning of day 9 and grab a tuk-tuk or taxi to your hotel (haggle for the price). I stayed at the Bed and Terrace Guesthouse and was lucky enough to have a balcony with gorgeous mountain views. Grab some breakfast and take a wander around Chiang Mai to get acquainted with your surroundings. Visit Chiang Mai Night Bazaar which is perhaps one of the most epic night markets in Southeast Asia!

Tip: When you arrive at Chiang Mai train station there will be a lot of taxi drivers waiting outside. Research up to date taxi prices before you get to Chiang Mai and make sure you barter for the fare to your hotel. Unlike other parts of Thailand, they do not use meters here.

Day 10 and 11: Spend two days doing some of the best things to do in Chiang Mai. Chat with a monk to learn about their way of life and visit some beautifully intricate temples like Wat Chiang Man. Walk around the outside of the moated city walls. Feast on northern Thai cuisine and become captivated by the cool-as-a-cucumber aura that permeates the city.

Wat Chadi Luang in Chiang Mai, Thailand
Wat Chedi Luang in Chiang Mai
Chiang Mai Night Bazaar
Intricate candles at Chiang Mai Night Bazaar

Day 12: Today, book to go ziplining high above the jungle canopy. If you’re lucky, you might spot some monkeys. In the evening, why not head to watch some traditional Thai Boxing?

Tip: Make sure you do your research and book a ziplining tour with a reputable company. Don’t compromise on your safety for the sake of saving a few Thai Baht.

Elephant Nature Park in Chiang Mai, Thailand
Elephant Nature Park in Chiang Mai - 3 weeks in Thailand

Day 13: Spend day 13 of your 3 weeks in Thailand enjoying an ethical elephant experience at Elephant Nature Park. Make sure you go to a sanctuary where the elephants are safe and free from abuse. Riding elephants in Thailand exacerbates the illegal trade of these gentle giants around Southeast Asia and they are often mistreated. Avoid this, and contribute to something sustainable and ethical instead.

Krabi: Day 14-16

Krabi is an idyllic province located in southern Thailand where limestone karsts covered in dense green jungle erupt from the land and the clear waters of the ocean…. Where sandy beaches decorated with long-tail boats are lapped by the Andaman Sea… And where a population of long-tailed macaques call home. The friendly and picturesque resort town of Ao Nang is a beautiful place to visit for a few days out of your 3 weeks in Thailand. Due to the many long-tail boats that act as water taxis to neighbouring places such as Railay, it’s a great town to base yourself for exploring the area. Plus there is no shortage of bars, restaurants, and shops to keep you entertained at night!

Ao Nang Beach in Krabi, Thailand
Ao Nang Beach in Krabi province

Day 14: Board a morning flight from Chiang Mai to Krabi. When you land, take a pre-booked private transfer to your hotel with Krabi Shuttle. I stayed at Timber House Ao Nang and loved the pool and room terrace. After checking in, take a wander to Ao Nang beach, and on your way, stop by a local tour operator and book a shared transfer to Phuket for the morning of day 17 (it’s good to be organised in case this get fully booked). Enjoy Ao Nang beach and the views of the limestone karsts in the distance. Head to Crazy Gringos for a cold Chang or two, or enjoy a cocktail at a beach bar whilst the sun goes down.

Tip: Morning flights tend to be a little more expensive than later ones. But its worth the extra Baht, Euros, Dollars, or Pounds to maximise your time in each destination. Hanging around throughout the morning whilst waiting for a later flight is no fun. And it makes the day pass by slowly when you could be fully enjoying your next stop!

Railay beach in Thailand
Railay Beach in Krabi

Day 15: Wade through the sea and board a long-tail boat around to relaxed Railay where you will spend the day. Watch out for the monkeys, and the tiny white crabs that hide in the sand (you will see all the pin sized holes across the sand, and you might see them pop out). Enjoy some lunch and spend the day wandering the area, finding various beaches as you go, before returning back to Ao Nang by boat.

Day 16: Pencil in day 16 of your 3 week Thailand itinerary for some relaxation by Ao Nang beach or your hotel pool! Travelling around Thailand can be a tiring feat, and the southern part of the country is perfect for some down time! Remember, it’s important to slow down!

Phuket: Day 17-20

Phuket is Thailand’s largest island connected to the mainland by Sarasin Bridge, and offers a diverse array of resorts, towns and secluded areas to stay. Abundant with palm-lined beaches, jungles, and temples, it is the perfect place to add a pinch of relaxation to your itinerary for the last few days of your 3 weeks in Thailand. For my few days in Phuket, I chose to stay in the quiet area of Karon Beach (which, as it says on the tin, has the most gorgeous sandy beach). Although more tranquil than its rowdy neighbour Patong, it still has a range of boutique hotels and quality restaurants.

Ao Phang Nga National Park - 3 weeks in Thailand
Ao Phang Nga National Park in southern Thailand

Day 17: You know that shared transfer from Ao Nang to Phuket you booked on day 14 because you were super organised? Jump in that this morning bound for Phuket (this will take a few hours). Once you arrive, check in to your hotel, have some lunch and then spend the afternoon by the pool soaking up the Thai sunshine.

Day 18: On day 18 of your 3 weeks in Thailand, enjoy a day trip to the stunning Ao Phang Nga National Park, with its beautiful emerald green waters. Ao Phang Nga National Park is famous as the setting for The Man with the Golden Gun (hence the nickname of James Bond Island for one of it’s limestone karsts).

Day 19: Head to the beach or take a tuk-tuk to Patong. Patong is a lively place that requires an acquired taste, and if you are a party animal then you are probably going to love it here (personally, I wouldn’t go back and would suggest spending the day enjoying a more cultured experience). In the evening, go to Karon Temple Night Market held at Wat Suwan Khiri Khet (Tuesdays and Fridays only).

Day 20: You want some time to chill out, right? Remember, you don’t have to do everything at a million miles per hour. After all, your in the Southeast Asian paradise that is Thailand! You are nearing the end of your busy trip, so why not spend a day by the beach or pool before heading back to Bangkok?

Bangkok: Day 21-22

It’s time to head back to Bangkok for the final 2 days of your trip! Yes, you could fly back to Bangkok for your return flight home on day 22, but what if the flight is delayed, or even worse, cancelled? Expect the unexpected, have a plan B, and always have room to manoeuvre, because the last thing you want is to miss your flight home (or maybe you do, because you don’t want to leave Thailand, but you probably won’t want to pay out for a rescheduled flight)!

The Grand Palace, Bangkok
Decoration on the external walls at the Grand Palace, Bangkok

Day 21: Take a pre-booked private transfer to the airport with Phuket Shuttle and board a morning flight from Phuket to Bangkok. Transfer into the city by using the Bangkok Airport Rail Link, and then lose yourself in the chaos for a few hours before heading to dinner.

Tip: Stay in a hotel that is within walking distance of the Bangkok Airport Rail Link so you can board the train with ease on the morning of day 23 to get back to the airport, without having to worry about taxis! I chose to stay at iCheck Inn Mayfair Pratunam.

Day 22: Spend your last day in Bangkok visiting any of the sights you want to return to from your first few days in the city at the beginning of the trip, or any you didn’t quite manage to see. Perhaps do something relaxing like go for a massage. Grab any last minute souvenirs, enjoy the atmosphere, and indulge in some scrummy food at your final Thai feast of the trip!

Return home: Day 23

Day 23: Allow at least 1 full day to be lost for international travel from Southeast Asia if you are travelling from outside the region.

Thailand itinerary summary

This 3 week itinerary for Thailand is perfect for budget travellers and first timers alike who want to experience a bit of everything that Thailand has to offer – chaotic cities, ancient kingdoms, vibrant culture, extravagant temples, mountainous jungles, adventure, mouth-watering food, majestic wildlife, tropical beaches, and relaxation (and the list could go on). Taking you to central, northern and southern parts of Thailand in just 3 weeks, you will certainly get a good taste of what Thailand has to offer! And, the cherry on top is that this 3 weeks in Thailand can be done on a budget, which you will see when you check out my insane trip costs for this exact itinerary below!

Chiang Mai, Thailand

3 weeks in Thailand cost (per person)

International flights
Return flights from London Heathrow to Bangkok Suvarnabhumi Airport = £450.86pp

Regional flights (x2)
Hold luggage and meals included in prices

Chiang Mai International Airport to Krabi International Airport = £52.32pp
Phuket International Airport to Bangkok Suvarnabhumi Airport = £67.92pp

Other regional transport
Local train from Bangkok to Ayutthaya (one way) = £0.40pp
Overnight sleeper train from Ayutthaya to Chiang Mai = £26.12pp
Chiang Mai train station to hotel via tuk tuk = £1.30pp*
Ao Nang, Krabi to Karon Beach, Phuket via shared minibus transfer = £10.45pp

Airport transfers
Bangkok Airport to City via Airport Rail City Link (one way at start of trip) = £1.06pp
Chiang Mai hotel to Airport via taxi = £2.06pp*
Krabi International Airport to Ao Nang by private transfer (one way) = £7.83pp*
Karon Beach, Phuket to Phuket International Airport by private transfer = £11.10pp*
Bangkok Airport to City via Airport Rail City Link (return journey at end of trip) = £2.12pp

All hotels, no hostels

Bangkok 4 nights in a hotel inc. breakfast and use of pool = £70.50pp*
Ayutthaya 2 nights = £13.00pp*
Ayutthaya hotel room (for use during the day before overnight train on day 8) = £3.00pp*
Chiang Mai 5 nights = £29.50pp*
Ao Nang, Krabi 3 nights inc. use of pool = £43.00pp*
Karon Beach, Phuket 4 nights inc. use of pool = £26.00pp*
Bangkok 2 nights (before returning home) inc. breakfast = £35.00pp*

Total = £853.54 per person (~$1199.00pp)
for 3 weeks travel around Thailand!

*The cost for anything marked with an asterisk is per person (pp) based on 2 people sharing.

Note: Price excludes the costs for travel insurance, spending money (tours, food, occasional taxis, drinks etc.), costs to travel to/from UK airport for international flights, and visas (if required). I don’t book accommodation based on star rating, and book purely based on reviews, location and value for money. All accommodation is private hotel rooms (I’m not a hostel type of girl, I like my privacy and home comforts) or apartments, and all flights are economy. Prices for certain things may have changed since the time I took this trip, so please only use this as a guide to help you set your own savings target.

Pssst… sharing’s caring! Pin this post using one of the images below, so you can find it easily later!

3 weeks in Thailand
3 weeks in Thailand