Thailand's rail system operates under the State Railway of Thailand, established in 1890 under King Rama V. The network spans approximately 4,500 kilometers across four main lines: Northern Line to Chiang Mai (751 kilometers from Bangkok), Northeastern Line to Nong Khai on the Laos border (624 kilometers), Eastern Line to Aranyaprathet at the Cambodia border (255 kilometers), and Southern Line to Hat Yai and the Malaysian border (1,159 kilometers). Bangkok's Hua Lamphong station, opened in 1916, served as the central terminus until partial operations shifted to Bang Sue Grand Station in January 2021. Bang Sue Grand Station covers 280,000 square meters and stands as Southeast Asia's largest railway station.
The Northern Line from Bangkok to Chiang Mai operates five daily departures. The fastest service, Train 7 Special Express, completes the journey in approximately 11 hours overnight. Second-class sleeper berths cost between 791 and 881 baht depending on upper or lower position. First-class cabins with two berths range from 1,353 to 1,453 baht. The route passes through Ayutthaya, Lopburi, Phitsanulok, and Lampang. Trains 109 and 111 offer daytime services taking approximately 13-14 hours with seated coaches only.
The Northeastern Line connects Bangkok to Nong Khai via Nakhon Ratchasima and Udon Thani. Train 25 departs Bangkok at 20:00 and arrives in Nong Khai at 06:40, covering 624 kilometers in approximately 10 hours 40 minutes. Second-class air-conditioned sleepers cost 798 baht for upper berths and 888 baht for lower berths. The route serves Nakhon Ratchasima (259 kilometers from Bangkok) as the gateway to the Khorat Plateau, with arrival approximately 4 hours after departure.
The Southern Line divides at Hat Yai, with branches continuing to Sungai Kolok on the eastern Malaysia border and Padang Besar on the western Malaysia border. Train 45 departs Bangkok at 14:45 and reaches Hat Yai at 11:30 the following day, covering 945 kilometers. Second-class sleeper fares to Hat Yai cost 848 to 938 baht. The route serves Hua Hin (229 kilometers, approximately 4 hours), Chumphon (485 kilometers, approximately 8.5 hours), and Surat Thani (651 kilometers, approximately 11 hours). From Surat Thani, bus and ferry connections reach Koh Samui and Koh Phangan.
The Eastern Line terminates at Aranyaprathet near the Cambodia border crossing to Poipet. Third-class ordinary trains depart Bangkok's Hua Lamphong at 05:55, reaching Aranyaprathet at 11:35 for 48 baht. The single daily service uses non-air-conditioned cars with wooden bench seating.
The Bangkok Mass Transit System (BTS Skytrain) opened its first lines on December 5, 1999. The elevated system operates two lines: the Sukhumvit Line running 25 stations from Khu Khot to Kheha, and the Silom Line running 14 stations from National Stadium to Bang Wa. Trains run from 06:00 to 24:00 with frequencies of 3-5 minutes during peak hours. Single-journey tickets cost 16-59 baht depending on distance. The Rabbit Card stored-value card deducts fares electronically. Extensions opened in 2020 added 11 stations to northern suburbs.
The Metropolitan Rapid Transit (MRT) underground system opened its Blue Line on July 3, 2004, running from Tha Phra to Lak Song via Hua Lamphong and Sukhumvit. The Blue Line operates 38 stations across 48 kilometers. The Purple Line opened in August 2016, connecting Tao Poon to Khlong Bang Phai in Nonthaburi Province with 16 stations across 23 kilometers. Single-journey tokens cost 16-42 baht. MRT operates from 06:00 to 24:00 with peak-hour frequencies of 4-6 minutes.
The Airport Rail Link connects Suvarnabhumi Airport to central Bangkok. The Express Line operated direct service to Makkasan station in 15 minutes until suspension in 2015. The City Line operates eight stations from Suvarnabhumi to Phaya Thai, completing the 28.6-kilometer route in approximately 30 minutes. Service runs 06:00 to 24:00 with frequencies of 10-15 minutes. Fares range from 15 to 45 baht depending on distance. Phaya Thai station connects to BTS Sukhumvit Line for onward travel.
The Transport Company Limited, a state enterprise under the Ministry of Transport, operates intercity bus services nationwide. Bangkok's three main bus terminals serve different regions: Mo Chit 2 (northern and northeastern routes), Sai Tai Mai (southern routes), and Ekkamai (eastern routes). Government buses display orange license plates and operate in several classes: regular non-air-conditioned (cheapest), second-class air-conditioned, first-class air-conditioned, and VIP 24-seat configuration.
Bangkok to Chiang Mai covers approximately 700 kilometers via Highway 1 and Highway 11. Government first-class buses depart Mo Chit 2 terminal between 19:00 and 21:00, arriving approximately 10-11 hours later. Fares cost 573-681 baht for first-class air-conditioned service. VIP 24-seat buses with more legroom and fewer stops cost 822-927 baht. Private operators including Nakhonchai Air and Sombat Tour operate competing services from 600 to 1,200 baht depending on configuration. Sombat Tour's VIP buses feature seats that recline to near-flat positions.
Bangkok to Phuket via Sai Tai Mai terminal covers approximately 840 kilometers via Highway 4 through Chumphon and Ranong. Government first-class services depart between 18:00 and 20:00, arriving approximately 12-13 hours later for 714-896 baht. Private operators offer VIP services with toilet-equipped buses for 900-1,400 baht. The route serves Hua Hin (3.5 hours, 220-280 baht), Chumphon (7-8 hours, 450-550 baht), and Ranong (9-10 hours, 550-650 baht).
Bangkok to Nakhon Ratchasima operates from Mo Chit 2 terminal covering 259 kilometers via Highway 2. Buses depart every 30 minutes from 03:30 to 23:00. Second-class air-conditioned services take approximately 4 hours for 206-244 baht. First-class buses complete the journey in 3.5 hours for 286-321 baht. Nakhon Ratchasima serves as the hub for onward connections to Khao Yai National Park (80 kilometers north).
Chiang Mai to Chiang Rai covers 180 kilometers via Highway 118. Green Bus Company operates this route with departures every hour from 06:00 to 17:30 from Chiang Mai Arcade Bus Station. First-class air-conditioned buses take approximately 3 hours for 145-178 baht. The route passes through Mae Chan district with mountain views approaching Chiang Rai.
Phuket to Krabi operates via Highway 4 covering approximately 160 kilometers. Services depart Phuket Bus Terminal 2 every 45 minutes from 06:30 to 18:30. Second-class air-conditioned buses take approximately 3-3.5 hours for 150-180 baht. The route serves Phang Nga (80 kilometers, 1.5 hours, 80-100 baht) before continuing to Krabi.
Bangkok operates an extensive local bus network under the Bangkok Mass Transit Authority with over 400 routes identified by number. Air-conditioned buses (cream and blue) charge flat fares of 11-25 baht depending on route. Non-air-conditioned buses (red and cream) charge 6.50-8 baht. Route 29 connects Hua Lamphong railway station to Lak Si via Sukhumvit Road. Route 15 runs from Sanam Luang past Democracy Monument and Victory Monument to Ramkhamhaeng Road. Route numbers below 60 operate 24 hours. Buses display route numbers and terminus names in Thai script on the front, with some showing English translations. The BMTA system carried approximately 1.9 million passengers daily before ridership decline from 2010 onward as rail transit expanded.
Songthaews function as shared taxis in many Thai cities. These converted pickup trucks with two bench seats in the cargo bed operate on semi-fixed routes. In Chiang Mai, red songthaews charge 30 baht for trips within the old city moat area and 40-60 baht for longer distances. Passengers flag them from the roadside and ring a bell to signal stops. In Phuket, blue songthaews serve specific routes including Phuket Town to the beaches, with fixed fares of 30-50 baht. Hat Yai operates green songthaews on routes throughout the city for 15-25 baht.
Bangkok operates two commercial airports. Suvarnabhumi Airport opened September 28, 2006, replacing Don Mueang as the primary international gateway. Suvarnabhumi handled 60 million passengers in 2018 across two terminals covering 563,000 square meters. The airport code is BKK. Don Mueang Airport, originally opened in 1914 and expanded as Thailand's main airport until 2006, reopened for domestic flights in March 2007 and later added low-cost international services. Don Mueang uses airport code DMK and handled 38 million passengers in 2018, primarily operating budget carriers including Nok Air, Thai AirAsia, Thai Lion Air, and Thai VietJet Air.
Thai Airways International serves as the national flag carrier, founded in 1960. The airline operates domestic routes from Suvarnabhumi Airport to 11 destinations including Chiang Mai, Phuket, Krabi, Hat Yai, Chiang Rai, Udon Thani, Khon Kaen, Ubon Ratchathani, and Surat Thani. Bangkok Airways, founded in 1968, operates a hub at Suvarnabhumi with domestic services to Koh Samui, Sukhothai, Trat, Lampang, and Krabi. Bangkok Airways owns and operates Koh Samui Airport, opened in 1989 as an open-air terminal with grass-roofed buildings. The airline maintains a virtual monopoly on Koh Samui routes.
Thai AirAsia commenced operations in 2004 as a joint venture bringing the Malaysian low-cost model to Thailand. The carrier operates from Don Mueang to 24 domestic destinations. Bangkok to Chiang Mai operates 16-20 daily flights taking 1 hour 20 minutes. Advance-purchase fares start at 590 baht before taxes and fees, with final prices ranging from 900 to 1,800 baht depending on booking timing. Bangkok to Phuket operates 18-22 daily flights with a flight time of 1 hour 25 minutes. Advance fares begin at 690 baht before fees.
Nok Air, established in 2004 as a subsidiary of Thai Airways, operates low-cost services from Don Mueang to 21 domestic points. Bangkok to Udon Thani flies 6-8 times daily, covering 450 kilometers in 1 hour 10 minutes for 900-1,600 baht including fees. Bangkok to Hat Yai operates 5-7 daily flights taking 1 hour 35 minutes for 1,100-2,200 baht. The airline's name means "bird" in Thai, and aircraft feature bright orange and yellow beaks painted on the fuselage nose.
Thai Lion Air, the Thai subsidiary of Indonesian Lion Air, began operations in 2013. The carrier operates from Don Mueang to 15 domestic destinations. Bangkok to Chiang Rai operates 3-4 daily flights taking 1 hour 30 minutes for 1,000-1,800 baht. Bangkok to Krabi flies 3-4 times daily in 1 hour 20 minutes for 900-1,700 baht.
Chiang Mai International Airport, located 3 kilometers southwest of the city center, operates as northern Thailand's primary hub with airport code CNX. The airport handled 10.5 million passengers in 2018. Domestic terminals serve Thai Airways, Bangkok Airways, Thai AirAsia, Nok Air, Thai Lion Air, and Thai VietJet Air with connections to Bangkok, Phuket, Hat Yai, Krabi, Udon Thani, and Ubon Ratchathani. Chiang Mai to Phuket operates 2-3 daily flights taking 2 hours 10 minutes for 1,800-3,200 baht.
Phuket International Airport, 32 kilometers north of Phuket town, uses airport code HKT and handled 18.2 million passengers in 2018. Domestic flights connect to Bangkok (1 hour 25 minutes), Chiang Mai (2 hours 10 minutes), Hat Yai (1 hour), Koh Samui (50 minutes), and Udon Thani (1 hour 50 minutes). Phuket to Koh Samui operates 3-4 daily flights via Bangkok Airways for 2,200-3,800 baht. Bangkok Airways' monopoly on Koh Samui routes results in consistently higher fares compared to other domestic sectors.
Krabi Airport, located 15 kilometers east of Krabi town, uses code KBV and handled 4.4 million passengers in 2018. Domestic services connect to Bangkok (9-11 daily flights, 1 hour 20 minutes, 900-2,000 baht), Chiang Mai (1 daily, 2 hours 15 minutes, 2,000-3,500 baht), and Phuket (seasonal service, 35 minutes).
Hat Yai International Airport serves southern Thailand with airport code HDY, located 13 kilometers from Hat Yai city. Domestic flights operate to Bangkok (10-14 daily, 1 hour 35 minutes, 1,100-2,200 baht), Chiang Mai (1-2 daily, 2 hours 35 minutes, 2,500-4,000 baht), and Phuket (1 daily, 1 hour).
Udon Thani Airport uses code UTH and serves northeastern Thailand with connections to Bangkok (8-10 daily, 1 hour 10 minutes, 900-1,600 baht), Chiang Mai (1 daily, 1 hour 25 minutes, 1,800-2,800 baht), and Phuket (3-4 weekly, 2 hours 15 minutes, 2,200-3,500 baht).
Surat Thani Airport, code URT, is located 21 kilometers from Surat Thani town. Flights to Bangkok operate 6-8 times daily taking 1 hour 15 minutes for 1,000-1,900 baht. The airport serves as an alternative entry point for Koh Samui, with bus and ferry combinations available from the airport to the island in 3-4 hours total.
Trat Airport, 30 kilometers from Trat town, uses code TDX and operates primarily seasonal service. Bangkok Airways flies Bangkok to Trat once daily in 1 hour for 2,400-3,600 baht. The airport serves as access to Koh Chang and eastern islands.
Ferry routes connect the mainland to Thailand's islands in the Gulf of Thailand and Andaman Sea. Services operate year-round to major islands, with some routes suspended during monsoon season from May to October on the Andaman side and November to January on the Gulf side.