Thailand’s domestic flight network covers the whole country in under two hours from Bangkok to almost anywhere, but it runs through two different airports and six airlines with very different baggage rules, and mixing those up is the single most common way travellers lose money or miss a flight. This guide compares the six carriers side by side, walks through the DMK-versus-BKK airport trap, and lays out what checked and cabin baggage actually costs on each airline, plus typical fares, booking timing, and when flying is worth it over the bus or train.
Prices here are quoted in Thai baht (THB) with US dollars in parentheses at ฿33 = US$1 (July 2026), given as ranges because airfares and baggage fees change with season and demand. If you’ve just landed and need to get into the city before a domestic connection, see our Bangkok airport to city guide, and once you’ve picked your dates, our cheapest time to fly to Thailand guide covers seasonal fare patterns in more depth.
Thailand’s domestic airlines at a glance
| Airline | Base airport | Domestic network | Checked bag included? | Vibe |
|---|---|---|---|---|
| Thai Airways | Suvarnabhumi (BKK) | Chiang Mai, Phuket, Krabi, Hat Yai, Udon Thani and more | Yes, one bag up to 23kg in economy | Full-service, national carrier, priciest of the six |
| Bangkok Airways | Suvarnabhumi (BKK) | Koh Samui, Chiang Mai, Krabi, Trat (for Koh Chang), Sukhothai | Yes, 20kg in economy | ”Asia’s Boutique Airline,” lounge access on some routes, owns and controls Samui’s airport |
| Thai AirAsia | Don Mueang (DMK) | Around 22 domestic routes, one of the two widest budget networks | No on standard fares, buy in advance | Budget, no-frills, biggest low-cost route map alongside Nok Air |
| Nok Air | Don Mueang (DMK) | Up to 24 domestic destinations, Thailand’s most extensive domestic network | Depends on fare: Lite = 0kg, X-Tra = 15kg, Max = 25kg | Budget, red livery, tiered fare classes |
| Thai Lion Air | Don Mueang (DMK) | Around 15 domestic destinations | No on standard fares, buy in advance (usually cheapest per kilogram) | Ultra-budget, fewest frills of the group |
| Thai Vietjet | Suvarnabhumi (BKK) | Around 10 domestic destinations | Depends on fare: Eco = 0kg, Deluxe = 20kg, SkyBoss = 30kg | Budget, one of the few low-cost carriers based at Suvarnabhumi rather than Don Mueang |
Compiled from current airline baggage and route pages; allowances and route counts change as airlines adjust schedules, confirm at booking. ฿33 = US$1 (July 2026).
Which airline should you fly in Thailand?
It comes down to what you’re optimising for, price or included amenities, not which airline is objectively “best.” Thai Airways and Bangkok Airways cost more upfront but include a checked bag, more legroom, and a fuller service, worth it if you’re checking a normal-sized suitcase and want one predictable fare. Thai AirAsia, Nok Air, Thai Lion Air and Thai Vietjet post lower headline fares but strip out baggage, seat selection and sometimes snacks as add-ons, worth it if you’re travelling light or you factor the add-ons into your total cost before comparing. Bangkok Airways is also the only direct option to Koh Samui, since it owns the island’s airport outright, so if Samui is your destination, price comparison there is more limited than on routes with real competition.
Suvarnabhumi or Don Mueang: which airport does your flight use?
Check your ticket, not your assumption, because Bangkok’s two airports handle almost entirely different airlines. Suvarnabhumi (BKK) is the country’s main international gateway and the base for Thai Airways, Bangkok Airways, and Thai Vietjet’s domestic flights. Don Mueang (DMK) is Bangkok’s dedicated low-cost hub, home to Thai AirAsia, Nok Air and Thai Lion Air. The two airports sit roughly 25km apart, a 45-minute to 1.5-hour taxi ride depending on Bangkok traffic, with no train link or walkway between them and no way to transfer without leaving security at one and clearing it again at the other. Our Suvarnabhumi airport and Don Mueang airport guides cover each in more detail. The classic mistake is booking an international arrival into one airport and a domestic onward flight from the other the same day, assuming “Bangkok” means one location, then discovering the connection needs a taxi across the city rather than a walk between gates. If your itinerary has a same-day domestic connection, confirm the three-letter airport code (BKK or DMK) on both tickets before you build your transfer time around it.
Do budget airlines include checked baggage?
No, not on their cheapest fares, and this is where new flyers lose the most money. Thai AirAsia and Thai Lion Air sell every kilogram of checked baggage as an add-on, with no free allowance bundled into a standard fare. On Thai AirAsia’s domestic routes, a pre-booked 20kg checked bag runs about ฿663 (US$20) if bought during or shortly after booking, but jumps to about ฿900 (US$27) if bought at the airport counter within four hours of departure, and unbought excess baggage costs ฿300 (US$9) per kilogram. Thai Lion Air’s pattern is similar, prepaid baggage runs roughly 30 baht per kilogram if bought in advance, while unbought excess at the airport costs ฿350 (US$11) per kilogram. Nok Air and Thai Vietjet bundle baggage into fare tiers instead: Nok Air’s entry-level Lite fare includes no checked bag (adding 15kg costs roughly ฿430/US$13, 40kg roughly ฿1,155/US$35), while its X-Tra and Max fares include 15kg and 25kg respectively. Thai Vietjet’s Eco fare includes no checked bag either, with a minimum 15kg package purchased separately and added in 5kg increments, while its Deluxe (20kg) and SkyBoss (30kg) fares include baggage. The rule across all four: buy your baggage online, in advance, every time. The airport rate is always the punitive one.
How strict is the 7kg cabin bag limit?
Strict enough to plan around, even though enforcement isn’t identical every time. All four budget carriers cap cabin baggage at 7kg for one main bag plus one small personal item, and gate staff sometimes weigh bags directly rather than just checking them against a sizer frame, enforcement varies by airport and by which staff are working that flight, but travellers have reported bags being pulled and weighed even when they fit the size limit fine. Thai AirAsia formally charges a per-kilogram excess fee (around ฿80/US$2.40 per kilo, up to 3kg over) for an overweight cabin bag rather than simply refusing it, which confirms the weighing is a real, priced part of their process, not just an occasional spot check. Don’t assume a cabin bag is fine just because it fits in the overhead locker if you know it’s genuinely over 7kg.
How much do domestic flights in Thailand cost?
Fares move constantly with season, demand and how far ahead you book, but the broad ranges hold steady. Bangkok-Chiang Mai and Bangkok-Phuket, the two busiest domestic routes, typically run one-way fares of roughly ฿1,000-3,600 (US$30-110), with budget carriers at the low end and Thai Airways or Bangkok Airways at the high end; both routes take around 1 hour 20 minutes to 1 hour 30 minutes in the air. Bangkok-Koh Samui is the outlier: Bangkok Airways owns Samui’s airport outright and has no direct competitor on the route, so one-way fares typically run higher, roughly ฿2,300-4,800 (US$70-145). A cheaper workaround exists if you’re flexible: fly into Surat Thani instead, where AirAsia, Nok Air and Thai Lion Air compete for roughly ฿650-1,150 (US$20-35) one-way, then take a 1.5-2 hour ferry across to Samui, our getting to Koh Samui guide covers that transfer in full.
When should you book?
Book around a month ahead of a popular route for the best mix of price and flight-time choice, fares tend to climb steadily as a flight fills and jump sharply in the final week before departure. Booking directly through the airline’s own site is usually cheaper once you account for a third-party aggregator’s added service and payment fees, and it’s the only place you see the airline’s real baggage add-on pricing at the point of booking rather than a marked-up version bundled in later. If your dates are flexible, our cheapest time to fly to Thailand guide breaks down which months carry the lowest fares across the country.
What ID do you need?
Just your passport. Every domestic flight in Thailand requires foreign travellers to present a passport at both security screening and the boarding gate, alongside your printed or digital boarding pass, there’s no domestic exception the way there might be in some other countries. Thai nationals can use a Thai national ID card instead. Keep your passport accessible in your carry-on rather than buried in checked luggage on any day you have a domestic flight.
Are domestic flights often delayed?
Delays happen, and it’s worth being honest about it rather than pretending Thai domestic aviation runs on rails. Budget carriers in particular have gone through periods of publicised disruption, including route suspensions tied to rising fuel costs and technical issues grounding individual aircraft. Weather adds a seasonal layer: the rainy season, roughly August through October, brings afternoon thunderstorms that can push back departures, and the northern smoke season, February through April, occasionally cuts visibility enough to affect flights into Chiang Mai and Chiang Rai. None of this should put you off flying domestically, delays are the exception rather than the rule, but build a genuine buffer into any itinerary where a domestic flight connects to an international one on the same day, rather than booking the tightest layover the schedule allows.
Is flying worth it over the bus or train?
Yes, once the overland alternative runs past roughly 8-10 hours, or your destination is an island only reachable by a flight-plus-ferry combination. Bangkok to Phuket, for instance, is a 12-hour-plus drive or overnight train against a roughly 1.5-hour flight, and Bangkok to Chiang Mai is 9-10 hours by train against 1 hour 20 minutes in the air. For shorter routes with a solid direct train or bus, Bangkok to Ayutthaya or Bangkok to Hua Hin among them, ground transport is usually cheaper, just as reliable, and skips airport check-in and security entirely.
The honest downsides
Budget carriers will not warn you clearly enough that your fare excludes baggage, the checkout flow often defaults to no checked bag and it’s easy to miss until you’re at the airport paying the punitive rate. Suvarnabhumi and Don Mueang are genuinely separate airports, not two terminals of one complex, and no one will remind you which one your ticket uses. Cabin bag weight checks are inconsistent but real, don’t gamble on a bag you know is over 7kg. And delays cluster around the rainy season and, in the north, the smoke season, so build in buffer time during those windows rather than assuming every domestic hop runs exactly on schedule.
Where to next
Once your domestic flight is booked, sort the rest of the logistics: our Suvarnabhumi airport and Don Mueang airport guides cover check-in, transfers and facilities at each, and Bangkok airport to city covers getting from either one into town. If your dates aren’t fixed yet, our cheapest time to fly to Thailand guide breaks down seasonal pricing patterns in more depth. And once you’ve landed, browse what’s on right now in Thailand events.
Sources
- AirAsia fees and charges and domestic route baggage fee schedule (2026).
- Thai Vietjet baggage policy (2026).
- Thai Lion Air baggage allowance (2026).
- Nok Air baggage information (2026).
- Bangkok Airways baggage allowance (2026).
- Thai Airways checked baggage and piece concept announcement, effective March 2026.
- Current fare-aggregator listings (Skyscanner, Expedia, Trip.com) for Bangkok-Chiang Mai, Bangkok-Phuket and Bangkok-Koh Samui routes (2026).
- Reporting on 2025-2026 domestic route suspensions and delays affecting Thai budget carriers (Bangkok Post, The Thaiger).