Thailand Domestic Flights Guide: Airlines, Routes & Prices

A one-hour flight from Bangkok to Chiang Mai on a low-cost carrier often costs less than £30, saving you a gruelling twelve-hour overnight train journey. However, turning up at the wrong Bangkok airport or miscalculating your baggage allowance can instantly wipe out those savings.

This guide explains exactly how to navigate Thailand’s domestic aviation network so you can book the right flights with confidence. You will learn the critical differences between budget and full-service airlines, which routes operate from Suvarnabhumi versus Don Mueang airports, and how strict baggage limits actually are. It provides realistic pricing, route breakdowns for major hubs like Phuket and Koh Samui, and practical advice on avoiding common booking traps.

Choosing Your Bangkok Airport

Bangkok operates two separate airports positioned thirty miles apart, and your choice dictates which airlines you can fly. Suvarnabhumi (BKK) is the primary international hub located east of the city. If you are arriving from London Heathrow on Thai Airways or EVA Air and connecting immediately to Phuket or Chiang Mai, you want to fly out of BKK. Thai Airways, Bangkok Airways, and Thai Vietjet operate their domestic routes from here. Don Mueang (DMK), located to the north, is the dedicated low-cost carrier hub. This is the domain of Thai AirAsia, Nok Air, and Thai Lion Air. Getting between the two airports takes at least an hour on the free shuttle bus, or considerably longer in heavy traffic. Do not assume your domestic flight departs from the same airport you arrived at. Booking a domestic flight from DMK when your international flight lands at BKK leaves you rushing across a highly congested city with all your luggage. Always check the airport code before paying for a domestic ticket out of Bangkok.

Budget vs Full-Service Airlines

The Thai domestic market splits sharply between ultra-low-cost carriers and premium regional airlines, with a vast difference in base inclusions. Budget airlines like Thai AirAsia, Nok Air, and Thai Lion Air dominate the skies with fiercely competitive base fares. Thai AirAsia serves over 20 domestic destinations from its Don Mueang hub, Nok Air covers a similar network from the same base, and Thai Lion Air focuses on the busiest trunk routes — checking each airline's own route map directly is worth it if your destination isn't one of the routes named below.

As a benchmark, a Bangkok–Chiang Mai budget fare typically runs 1,000–3,000 THB (£22–£67) depending on how far ahead you book and the season, while the same route on a full-service carrier like Bangkok Airways or Thai Airways runs closer to 2,600–4,000 THB (£58–£90) with checked baggage included.

A standard ticket gets you a seat and 7kg of cabin baggage, with absolutely everything else costing extra. Checked luggage, seat selection, and even drinking water are chargeable add-ons. Full-service airlines operate entirely differently. Bangkok Airways promotes itself as a boutique airline and includes 20kg of checked luggage, free seat selection, in-flight snacks, and access to a departure lounge with free coffee and pastries for all economy passengers. Thai Airways offers a similar premium experience with generous luggage allowances depending on the ticket class. When you factor in the cost of adding a 20kg bag to a low-cost carrier—which typically costs 600 THB to 900 THB (£13.50 to £20) per sector—the price gap between a budget airline and a full-service carrier narrows significantly. Calculate the total cost including your checked baggage before assuming a budget carrier is the cheapest option.

For comparing fares across Nok Air, Thai Lion Air, and Thai AirAsia in one search, 12Go Asia is the standard cross-carrier booking tool used in Thailand — useful when an airline's own site or app is difficult to use from a UK card or number.

The Koh Samui Monopoly

Flying directly into Koh Samui is significantly more expensive than other Thai islands because Bangkok Airways owns the airport. As the private owner of Samui International Airport (USM), Bangkok Airways controls almost all landing slots. They operate a near-monopoly on the highly popular Bangkok to Koh Samui route, running dozens of flights a day. Because there is no low-cost competition on this direct route, a one-way ticket rarely drops below 3,500 THB (£78) and often exceeds 5,000 THB (£112) during peak UK winter travel months. The alternative is flying into Surat Thani (URT) or Nakhon Si Thammarat (NST) on the mainland using a budget carrier like AirAsia or Nok Air. These airlines sell combined flight and ferry tickets where a coach meets your plane and takes you to the pier for a catamaran crossing to Samui. While mainland flights cost around 1,000 THB to 1,500 THB (£22 to £33), the bus and ferry transfer adds at least four hours to your total journey time. Pay the premium for a direct Samui flight if your holiday time is short, but take the mainland ferry route if your budget is strict.

Key Regional Routes Avoiding Bangkok

You do not always need to transit through the capital, as direct regional flights connect Thailand's north and south. The most valuable domestic route for UK travellers is the direct flight between Chiang Mai (CNX) and Phuket (HKT). Thai AirAsia operates this two-hour sector daily, allowing you to move directly from the northern mountains to the Andaman coast without wasting half a day connecting in Bangkok. Expect to pay between 2,000 THB and 3,500 THB (£45 to £78) for this direct service. Similar direct coastal routes exist from Chiang Mai to Krabi (KBV) and Surat Thani (URT). Bangkok Airways also operates a highly useful direct flight between Phuket and Koh Samui, linking the Andaman Sea to the Gulf of Thailand in just under an hour. This saves an entire day of overland bus travel and ferry crossings. These regional point-to-point flights operate less frequently than Bangkok routes, sometimes only once a day, meaning they sell out much faster during the December to February high season. Book direct regional flights between the north and the islands at least a month in advance to secure a seat.

Baggage Rules and Strict Enforcement

Thai domestic airlines enforce their baggage weight limits rigorously, and excess fees at the check-in desk are heavily penalised. Every low-cost carrier in Thailand limits cabin baggage to a strict 7kg maximum. This usually includes both your overhead bag and your personal item combined. Staff at Don Mueang and Phuket airports frequently weigh cabin bags at the boarding gate, especially on fully booked flights. If you are caught over the limit, you will be forced to check the bag at a penalty rate of up to 1,500 THB (£33). When purchasing checked luggage online, you must select the correct weight tier. Buying 15kg during your initial booking might cost 500 THB (£11). Adding it later via the airline's app costs slightly more. Doing it at the airport counter on the day of departure is easily triple the price. Keep in mind that UK travellers arriving with a 23kg long-haul suitcase will need to deliberately purchase a 25kg allowance on low-cost domestic flights, as the standard pre-bookable tier is often only 15kg or 20kg. Always pre-purchase enough checked luggage allowance online during your initial booking to cover your heaviest suitcase.

Delays, Cancellations, and Your Rights

Thailand's domestic flight delays fall under Regulation of the Civil Aviation Board No. 101, in force since 20 May 2025. For a domestic flight delayed more than 3 hours, the airline must offer you rebooking onto an alternative flight. Past 5 hours, you become entitled to 1,200 THB (£27) in compensation regardless of the cause. If your flight is cancelled outright, compensation rises to 1,500 THB (£33) — unless the airline notified you at least 3 days in advance, offered an alternative within 3 hours of your original time, or the cancellation was due to weather or other circumstances outside its control. The airline must let you choose how you're paid: cash, a travel voucher, a credit shell, or frequent-flyer miles — it cannot decide this for you. If an airline refuses to honour these rights, file a complaint directly with the Civil Aviation Authority of Thailand at complaint.caat.or.th.

How to Book and Payment Methods

Booking directly through the airline's official website or application is always the safest method for securing domestic flights in Thailand. Third-party booking agencies often display slightly cheaper headline fares, but they complicate the process of adding baggage or changing your flight date later. When you book directly with Thai AirAsia or Bangkok Airways, you receive a direct booking reference that allows you to manage your trip via their official platforms. Payment can sometimes be an issue for UK travellers. Thai airline websites frequently trigger fraud alerts on British bank cards because the transaction processes in Bangkok. To prevent your payment from declining at checkout, notify your bank via their app before making the purchase, or use a dedicated travel card. Always opt to pay in Thai Baht (THB) rather than allowing the website to convert the price into GBP. The airline's dynamic currency conversion rate is notoriously poor, and paying in the local currency ensures you get the real exchange rate from your card provider. Book directly with the airline and pay in Thai Baht using a fee-free travel card to secure the best overall price.

COSTS AND BUDGETING

Domestic flight pricing in Thailand operates on a dynamic model, rising sharply as the departure date approaches. If you book four to six weeks in advance, a one-way budget ticket from Bangkok to Chiang Mai or Phuket typically costs between 900 THB and 1,500 THB (£20 to £33). This is the base fare, so expect to add around 600 THB (£13.50) for a 20kg checked bag. Mid-range options usually involve adding seats, bags, and meals to a budget carrier, bringing the total to around 2,200 THB (£49). Premium options mean flying full-service with Thai Airways or Bangkok Airways. These fares generally start from 2,500 THB (£56) for major trunk routes but jump to 4,500 THB (£101) or more for the monopoly route into Koh Samui. Booking during major Thai holidays like Songkran in April will see these prices double across all airlines.

Popular Domestic Routes at a Glance

The table below summarises the most frequently booked domestic routes for UK travellers, covering typical low-season starting fares and how often each route operates. Prices reflect budget base fares booked four to six weeks in advance and exclude checked baggage.

Bangkok to Phuket and Bangkok to Chiang Mai are the most competitively priced routes due to high frequency and multiple competing airlines. The Koh Samui route remains the most expensive due to Bangkok Airways' control of the airport, and the Chiang Mai to Phuket direct service, while pricier per kilometre, saves a full day versus connecting through the capital.

COMMON MISTAKES AND HOW TO AVOID THEM

Travellers often book their domestic connection from the wrong Bangkok airport. This guarantees a missed flight because transferring across the city takes over an hour. Always match your domestic departure code to your international arrival code.

Tourists frequently ignore the strict cabin baggage weight limits. Gate staff will weigh the bag and force a high penalty fee to check it. Pre-book checked baggage online if your gear exceeds seven kilograms.

Passengers blindly assume budget carriers are the cheapest option. Once mandatory bag and seat fees are applied, budget flights frequently match premium airline costs. Compare the final checkout price of both options before paying.

Foreigners occasionally attempt to board domestic flights using a UK driving licence. Airport security will deny you entry to the departure hall, leaving you stranded. You must present your physical passport to fly inside Thailand.

PRACTICAL TIPS

Check your departure terminal for Thai Airways flights at Suvarnabhumi. The airline occasionally uses the satellite terminal, which requires taking an underground automated train from the main concourse.

Download the airline application before you reach the airport. Budget airlines like AirAsia charge a fee to print boarding passes at the desk, so having the mobile QR code saves you money.

Carry a jumper or light fleece in your hand luggage. Thai airlines keep cabin air conditioning set aggressively low, making a one-hour flight feel freezing in shorts and a t-shirt.

Book morning flights during the wet season. Afternoon and evening departures face a much higher risk of delay due to the heavy thunderstorms that reliably roll in after 3:00 PM.

Leave your power banks in your cabin bag. Security strictly prohibits lithium batteries in checked luggage and will remove them from your suitcase before it reaches the plane.

Do not pack Buddha statues larger than twelve centimetres in your carry-on. Airport security enforces strict export and transport laws regarding religious artefacts and will confiscate oversized items at the scanner.

Arrive two hours early for domestic departures from Phuket during high season. The terminal becomes severely congested between December and March, meaning security queues alone can take forty-five minutes to clear.

Flight delays and lost baggage happen even on the best domestic routes.

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