Speed limits in Japan

Speed camera

A threshold for speed cameras in Japan is set at a minimum of 39 km/h (24 mph) above the limit on an expressway and a minimum of 29 km/h (18 mph) above the limit on other streets, where drivers will face criminal charges instead of traffic infractions. This is due to legal precedents dating back to 1969 restricting police from filming an individual unless a criminal offence is immediately being committed.

Police enforcement

Although there is no official tolerance for exceeding the speed limit, most drivers in Japan tend to drive over the speed limit on major roads. Police enforcement varies depending on the jurisdiction, officers, traffic flow and street types, but 19 km/h (12 mph) above the speed limit on an expressway and 14 km/h (8.7 mph) above the limit are generally tolerated on other streets.

In 2020, a total of 1,162,420 speeding tickets were issued across Japan, and only 199 tickets were issued for speeding between 0 and 14 km/h (0.0 and 8.7 mph) over the limit. Of the 199 tickets for speeding 0–14 km/h (0.0–8.7 mph) over the limit, Iwate Prefectural Police alone issued 166 tickets. For speeding between 15 and 19 km/h (9.3 and 11.8 mph) over the limit, Hokkaido, Aichi, Kyoto, Osaka and Fukuoka had the largest shares of tickets issued.

In contrast, Okinawa did not issue any tickets for speeding between 0 and 19 km/h (0 and 12 mph) over the limit. Tokyo Metropolitan Police issued a total of 68,693 speeding tickets, but gave out only seven tickets for speeding between 0 and 19 km/h (0 and 12 mph) over the limit. Some jurisdictions, such as Tokyo Metropolitan Police, release traffic enforcement locations on their websites.

Statutory speed limits provide the default limits, but posted regulatory speed limits are determined separately according to the design and use of the road. Japan distinguishes between surface streets (一般道路, ippan dōro) and expressways (高速道路, kōsoku dōro) in terms of speed limit regulations, with different criteria used to determine their regulatory speed limits.

Although some surface streets such as viaducts, trunk and bypass roads are built to expressway standards, many are not legally classified as expressways. They can generally be distinguished by the colour of direction signs: surface streets use blue direction signs while expressways use green signs.

Surface streets

Speed limits for surface streets are set within ±10 km/h (6.2 mph) of the reference speed limit below. Reference speed limits do not apply to expressways.

A speed limit may not exceed 60 km/h for streets with at-grade intersections or where pedestrians or cyclists are permitted. To exceed the 60 km/h threshold, the street must undergo costly grade separation to be a controlled-access highway.

Expressways

Although the speed limit on a divided expressway is normally subject to a maximum of 100 km/h (62 mph), a limit of up to 120 km/h (75 mph) may be set if it has low crash rates, both the lowest adaptation speed and design speed are 120 km/h, and the qualifying section is at least 20 km (12 miles) long. On an undivided expressway, the maximum speed limit set is 70 km/h (43 mph).

Expressway speed limits are determined using the lowest applicable "structure compatible speed" (構造適合速度, kōzō tekigō sokudo) criteria below, which is based on factors such as design speed and road geometry. Unlike surface streets, expressways are not subject to fixed range such as ±10 km/h around a reference speed. Regulatory limits may exceed the statutory limit where permitted by the road's criteria.

Intercity expressways typically have higher speed limits, while urban expressways within major cities often have a speed limit of 60 km/h (37 mph). Two-lane expressways, which are typically found in rural and remote areas, commonly have speed limits of 70 km/h (43 mph) where opposing traffic is separated only by delineator posts or similar devices, and 80 km/h (50 mph) where opposing traffic is physically separated.

Most expressways outside cities have active variable speed limit signs, with lower limits applied during congestions, accidents, constructions, severe weather, and other adverse conditions. When the statutory limit applies, the variable speed limit signs are left blank. Where the regulatory limit exceeds the statutory limit, separate variable speed limit signs may be used to display the lower limits applicable to certain vehicle types, including vehicles towing trailers and three-wheeled vehicles.

The speed limit is determined by the lowest applicable speed among the criteria below. Consequently, some four-lane expressways also have speed limits as low as 70 km/h.