Japan Expressway Rules: Max 100, Min 50 km/h, Who Can't Enter

Statutory expressway speeds by vehicle type

"Expressway" (高速道路) covers both national expressways (高速自動車国道) and motor-vehicle-only roads (自動車専用道路). The 100 km/h statutory limit applies only to the main lanes of national expressways and their acceleration/deceleration lanes (Enforcement Order Art. 27). Motor-vehicle-only roads have a statutory maximum of 60 km/h and no statutory minimum. In practice many sections have posted limits, and the sign then applies.

Kei cars (軽自動車) are legally standard motor vehicles, so they also get 100 km/h. Motorcycles get 100 km/h too.

Vehicles that may not use expressways

According to the Rules of the Road (交通の方法に関する教則), mini cars (ミニカー), small motorcycles (小型二輪車, i.e. standard motorcycles of 125 cc or less) and mopeds (一般原動機付自転車) may not use expressways (national expressways or motor-vehicle-only roads). Vehicles that by design cannot reach 50 km/h, or that cannot reach 50 km/h because they are towing another vehicle, may not use national expressways either.

A frequent false statement: "motorcycles of 125 cc or less may use expressways." Only motorcycles over 125 cc may.

Merging, lanes and shoulders

Expressway-specific bans trip up people who answer with ordinary-road habits.

• Merging: vehicles already on the main lane have priority. Merging vehicles must speed up fully in the acceleration lane and must not obstruct main-lane traffic (Road Traffic Act Arts. 75-6, 75-7)
• Lanes: drive in the leftmost lane as a rule. The passing lane (追越車線) is only for passing; return to the left promptly once you have passed (Art. 20)
• No crossing, U-turns or reversing on the main lanes, and no crossing the median. If you miss your exit, continue to the next interchange (Art. 75-5)
• Shoulders (路肩) and side strips (路側帯) are for emergencies such as breakdowns; never drive on them, even in a traffic jam
• Stopping and parking are banned in principle; when unavoidable, such as a breakdown, you may stop on a sufficiently wide shoulder (Art. 75-8)

Following distance, pre-trip checks and lights

On expressways you must keep enough distance to avoid hitting the vehicle ahead if it stops suddenly (Art. 26). NEXCO West Japan's guide: on a dry road with new tires, about 100 m at 100 km/h and about 80 m at 80 km/h; about twice that on wet roads or with worn tires.

Before entering an expressway, you must check fuel, coolant, engine oil and how your load is secured (Art. 75-10). Running out of fuel and stopping on the main lane can be a violation.

Even in daytime, when visibility is 200 m or less (50 m on ordinary roads) because of a tunnel or fog, you must turn on your headlights (Enforcement Order Art. 19).

Breakdowns and carrying a passenger on a motorcycle

If you have to stop on the main lane or the shoulder because of a breakdown, you must place a warning device (停止表示器材, such as a warning triangle) where drivers approaching from behind can see it (Art. 75-11; Enforcement Order Art. 27-6). At night, use the night-type device. Then everyone, including passengers, should move to a safe place such as behind the guardrail. See the "Accidents and emergencies" page for the full steps.

You may carry a passenger on a large or standard motorcycle on expressways only if you are 20 or older AND have held a motorcycle license for a total of 3 years or more (Art. 71-4). On ordinary roads the condition is 1 year of license history, so don't mix the two up.

Commonly mistaken patterns

Expressway questions typically swap numbers or flip who has priority.

• Kei cars are limited to 80 km/h on expressways → FALSE (now 100 km/h, same as standard cars)
• Large trucks are limited to 90 km/h → TRUE
• Tractor-trailers are limited to 80 km/h → TRUE
• Merging vehicles have priority and main-lane vehicles must yield → FALSE (main-lane traffic has priority)
• You may drive on the shoulder in a traffic jam → FALSE
• If you plan to pass again, you may stay in the passing lane → FALSE
• You may drive at 100 km/h even where a lower limit is posted → FALSE (signs take priority)

Check yourself with a mock test

Expressway questions become easy points once you know the table and the bans. You need 45 of 50 correct, so practice the number-swap questions with menkyopass's mock test in English.

Practice questions on this topic

• On the main lanes of a national expressway, the statutory minimum speed for standard motor vehicles (regular cars) is 50 km/h.
• On the main lanes of an expressway, you must not stop or park even in unavoidable situations such as a breakdown.
• Motorcycles with an engine size of 125 cc or less may use expressways.
• On the main lanes of a national expressway, the statutory maximum speed for light motor vehicles (kei cars) is 80 km/h.
• For a towing vehicle (such as a tractor-trailer) used to tow a broken-down car or similar, the statutory maximum speed on national expressways is 80 km/h.
• On the main lanes of a national expressway, the statutory maximum speed for large trucks is 90 km/h.
• When merging onto the main lanes of an expressway, the merging vehicle has priority, so vehicles on the main lanes must slow down and give way.
• On an expressway, you may drive on the road shoulder or side strip when traffic is congested.
• On an expressway, after overtaking the vehicle ahead, you may keep driving in the overtaking lane if you plan to overtake again.
• On the main lanes of an expressway, you must not make a U-turn, reverse, or cross the median strip.
• On an expressway section where a maximum speed is set by signs, you must follow the speed on the signs, not the statutory speed.

FAQ

Related guides

• Japan Speed Limits: 60 km/h, 30 km/h Residential Roads, Mopeds 30
• Accidents and Breakdowns in Japan: What to Do, Railroad Crossings
• Overtaking Rules in Japan: No-Overtaking Zones and Passing
• Japanese License Classes You Can Get by Converting (incl. AT)

Sources (in Japanese)

• e-Gov法令検索「道路交通法」（第20条・第26条・第71条の4・第75条の4〜第75条の11）
• e-Gov法令検索「道路交通法施行令」（第11条・第19条・第27条〜第27条の3・第27条の6。令和8年9月1日施行版）
• 警察庁「交通の方法に関する教則の一部を改正する件（令和8年国家公安委員会告示第32号）」（第7章 高速道路を通行できない車）
• 警察庁「生活道路の法定速度が30km/hになります」（60km/hのままの道路）
• NEXCO西日本「高速道路の走行ルール」（車間距離・路肩走行）