Driving is one of the ways to explore Thailand, especially in cities or towns where public transport is non-existent or rare, and even in areas where it is only accessible by car.

Understand

While tuk-tuks, buses, trains and motorcycle taxis are available in many cities in Thailand, the country has a strong car culture as well. However, traffic jams may occur in large cities including the capital city of Bangkok, so it is advised that you take public transport in these cities. However, in small cities and rural areas of Thailand, public transport may be infrequent or non-existent resulting in car dependency; thus a car is preferred to get around outside of Bangkok and other large cities.

Knowing a bit of Thai is useful, as the police rarely speaks any English or any other Western European language.

Road network

Thailand is widely described as having a good and most extensive road network in all of Southeast Asia with more than 390,026 kilometres (242,351 miles) of which 384,176 kilometres (238,716 miles) or 98.5 per cent are paved roads. The four main government-owned highway types are special highways, national highways, rural highways, local highways. The classification system is similar to those used in the United Kingdom, but it has no prefix letters at all.

• Special highways (ทางหลวงพิเศษ), also known as motorways, are high capacity highway designed for high-speed traffic.
• National highways (ทางหลวงแผ่นดิน) are primary highways that connect major regions, provinces, districts and other important destinations.
• Rural highways (ทางหลวงชนบท), also known as rural roads, are highways that serve as alternatives to national highways.
• Local highways (ทางหลวงท้องถิ่น), also known as local roads, are highways that link smaller settlements.

There are also concession highways (ทางหลวงสัมปทาน), which are state highways that are owned by a private sector.

One of the most important motorways in Thailand is Motorway 7, which is the Bangkok−Ban Chang Motorway (ทางหลวงพิเศษกรุงเทพมหานคร−บ้านฉาง), and connects Thailand's three most important cities: Bangkok, Chonburi and Pattaya.

Route numbers consist of between one and four digits. The first digit is the highway's serviced region of Thailand.

• 1 for Northern Thailand
• 2 for Isaan or Northeastern Thailand
• 3 for Central and Eastern Thailand
• 4 for Southern Thailand

The four important highway routes in Thailand you need to know are:

• Highway 1, Phahonyothin Road (ถนนพหลโยธิน): Bangkok – Chiang Rai
• Highway 2, Mittraphap Road (ถนนมิตรภาพ): Saraburi – Nong Khai
• Highway 3, Sukhumvit Road (ถนนสุขุมวิท): Bangkok – Trat
• Highway 4, Phet Kasem Road (ถนนเพชรเกษม): Bangkok – Sadao via Hat Yai

Keep in mind that Highway 2 does not reach Bangkok. If you try to take Highway 2 to Bangkok, you are going nowhere!

Units

Thailand uses metric units, and all distances on direction signs are posted in either metres or kilometres.

Road rules

Keep left

Keep left when driving in Thailand

While Thailand was never a British colony, the country drives on the left side like the United Kingdom, Ireland, Australia, New Zealand, Malaysia, Hong Kong and Japan. If you are used to driving on the right side, be sure to concentrate you do not accidentally veer to the wrong side.

Speed limits

The speed limit for motorways in Thailand is 120 km/h (75 mph), although as of 30 July 2022, new speed limits will be applied throughout Thailand, where regular cars will be subjected to the speed limit of 110 km/h (68 mph) on ground-level expressways. In built-up areas, the speed limit is 60 km/h (37 mph) and outside of built-up areas it is 80 km/h (50 mph). Speed limits are posted in kilometres per hour.

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  60 km/h (37 mph) for built-up areas
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  80 km/h (50 mph) for built-up areas
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  110 km/h (68 mph) on ground-level expressways
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  120 km/h (75 mph) on selected highways (the highest speed limit in Thailand)

Traffic lights

Only in some intersections of Thailand turns on red are illegal. In other intersections, turns on red are allowed.

Road signs

Road signs follow international convention, but borrows some elements from American and Japanese signage. For visitors from the United States, Canada, Australia and Europe, be aware that Thai road signage is closer to the one found in Latin America (such as the ones found in Brazil) than the one found in the U.S. or Europe. The Latin American signage colour system is typically followed in Thailand, and the distances shown are similar to the ones used in metric countries. The parking, no-entry and mandatory road signs are only a difference from the Latin American countries, the latter using a blue circle as in Europe, since 2004. Road signage is typically in Thai only, except in direction signs and in heavily-touristed areas, where English is shown in addition to Thai.

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  Stop
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  Give way (Yield)
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  The no entry is a white rectangle on a red background as in Europe.
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  Yellow diamonds are used for many warning signs, as in the U.S.
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  This no-overtaking zone sign is influenced by the U.S. but is pointing to the left. You cannot overtake when this sign is present.