Speed limitThailand

An introduction to the traffic rules and road signs of Thailand. Learn about driving, road safety and much more in our illustrated book, with answers to frequently asked questions.

For informational purposes only. Always follow official regulations. Some content and images were created with AI assistance.


2. Speed limit

A speed limit is the maximum legal speed permitted on a road, lane or within a designated area. It may be established by general traffic law or indicated by fixed, variable or temporary traffic signs.

A speed limit is a maximum, not a target speed. Drivers must travel more slowly whenever traffic, visibility, weather, road conditions, vulnerable road users or the condition of the vehicle make the maximum permitted speed unsafe.

50 km/h speed-limit sign with a curve warning. (Thailand)
Wikimedia.org • Thaweesak Churasri • CC BY
Which general speed limits should car drivers know in Thailand?

For an ordinary car, the national framework generally allows 80 km/h in specified urban areas and 90 km/h elsewhere, with separate categories and regulations for divided roads, expressways and motorways. Selected qualifying highways permit up to 120 km/h. Local rules can be substantially lower, including Bangkok’s general 60 km/h restriction with specified road exceptions. Follow the applicable signs and local conditions.

🔗 network.doh.go.th • 2021 designated-highway Regulation clauses 2–5; separate general framework and Bangkok restriction

🔗 laksong.metro.police.go.th • Official Police-hosted Gazette — full enacted Road Traffic Act amendment 13, 2022

🔗 aipalync.org • Council of State Thai Act consolidation through amendment 12 — read with full amendment 13

🔗 infocenter.oic.go.th • OIC official summary — 2021 speed frameworks and vehicle/road categories

🔗 upload.wikimedia.org • Royal Gazette facsimile of full 2021 general speed Regulation, mirrored PDF

🔗 ratchakitcha.soc.go.th • Royal Gazette — full December 2024 Bangkok speed and horn order

🔗 lopburi2.doh.go.th • DOH — February 2026 designated route notice, no nationwide 120 km/h assumption

Start of a speed limit. Start of a speed limit.

English • Traffic sign บ.32 • Speed limit: 50 km/h. Do not exceed 50 km/h and use a speed safe for road and traffic conditions.

ไทย • บ.32 • จำกัดความเร็ว 50 กม./ชม.. ห้ามขับรถด้วยความเร็วเกิน 50 กิโลเมตรต่อชั่วโมง และต้องใช้ความเร็วที่ปลอดภัยตามสภาพทางและการจราจร

Sources

🔗 Commons.wikimedia.org
🔗 Doh.go.th • กรมทางหลวง • คู่มือ พ.ศ. 2561 • เล่ม 1 • หน้า PDF 69

SVG source: Commons.wikimedia.org • Original SVG
Government of Thailand • Public domain • Original revision 2017-11-10. Wikimedia original unmodified.

Artwork reviewed against the Thai Department of Highways 2018 catalogue: Doh.go.th • PDF page 69. Catalogue-equivalent illustration; intentional update from the previous PNG. The catalogue depicts a variable speed value; the existing 50 km/h value is retained.

Does every divided Thai highway allow 120 km/h?

No. The 120 km/h arrangement applies only to qualifying, designated national or rural highway sections with at least two lanes in the same direction, a barrier median and no at-grade U-turn points. The competent highway director must designate the section. A central reservation or two lanes alone is insufficient. Follow the vehicle-category rules and applicable lower signs.

🔗 network.doh.go.th • 2021 designated-highway Regulation clauses 2–5; separate general framework and Bangkok restriction

🔗 laksong.metro.police.go.th • Official Police-hosted Gazette — full enacted Road Traffic Act amendment 13, 2022

🔗 aipalync.org • Council of State Thai Act consolidation through amendment 12 — read with full amendment 13

🔗 infocenter.oic.go.th • OIC official summary — 2021 speed frameworks and vehicle/road categories

🔗 upload.wikimedia.org • Royal Gazette facsimile of full 2021 general speed Regulation, mirrored PDF

🔗 ratchakitcha.soc.go.th • Royal Gazette — full December 2024 Bangkok speed and horn order

🔗 lopburi2.doh.go.th • DOH — February 2026 designated route notice, no nationwide 120 km/h assumption

1 Thailand 2 Speed limit 3 Minimum speed 4 Advisory speed 5 Slope 6 Stop sign 7 School area 8 Crossing animals 9 Curve 10 Roadworks 11 Traffic lights 12 Left-hand traffic 13 Driving licence 14 Reversing 15 Uncontrolled crossroad 16 Licence plate 17 Bus 18 Police 19 Ambulance 20 Pothole 21 Path 22 Particulates 23 Air pollution 24 Rush hour 25 Road code 26 Street gutter 27 Cargo bike 28 Lane splitting 29 Forestry vehicle 30 Construction vehicle 31 Semi-trailer truck 32 Trolleybus 33 Speed pedelec 34 Delivery vehicle 35 Idling 36 Tow truck 37 Four-wheel drive 38 Bicycle 39 Motorcycle equipment 40 Rail track 41 Caravan 42 Trailer 43 Tow hitch 44 Fire truck 45 Siren 46 Convoy 47 Emergency vehicle lighting 48 Agricultural machinery 49 Electric bicycle 50 Electric vehicle 51 Pedelec 52 Quadricycle 53 Microcar 54 All-terrain vehicle 55 Van 56 Recreational vehicle 57 Scooter 58 Trikke 59 Personal mobility device 60 Skateboard 61 Segway 62 Kick scooter 63 Roller skates 64 Mailman 65 Hitchhiker 66 Toddler 67 Child 68 Disability 69 Motorail 70 km/h 71 mph 72 Speedometer 73 Ride height 74 Dirt road 75 Driving 76 Start-stop system 77 Manual transmission 78 Automatic transmission 79 Throttle 80 Tachometer 81 Steering wheel 82 Power steering 83 Visual scanning 84 Mirror 85 Fuel 86 Fuel gauge 87 Petrol 88 Diesel 89 Diesel exhaust fluid 90 Car insurance 91 First aid kit 92 Fire extinguisher 93 High-visibility clothing 94 First aid 95 Concrete step barrier 96 Barriers 97 Vehicle lights 98 Street lights 99 Dipped beam 100 High beam ...