Speed limits in Japan

The highest speed limit in Japan is 120 km/h (approximately 74.6 mph), which applies on sections of Shin-Tōmei Expressway (E1A) and Tōhoku Expressway (E4), and expressways in the Kantō Plain leading to Tokyo, although a speed limit of 120 km/h is planned to be introduced on some more expressways.
Statutory speed limit defaults to 100 km/h (approximately 62.13712 mph) for national divided expressways or 70 km/h (43.5 mph) for undivided expressways, 30 km/h (approximately 18.64 mph) for undivided roads without center line (from September 1, 2026) and 60 km/h (approximately 37.3 mph) for any other roads (unless otherwise posted). Urban two-way streets are usually zoned at 40 km/h (24.855 mph) or less. However, the statutory speed limit for divided expressways is (since April 1, 2024) 90 km/h (56 mph) for a truck with GVWR over 8 t (17,640 lb) and a maximum load over 5 t (11,020 lb), and 80 km/h (49.71 mph) for motor vehicles with a trailer and three-wheelers (and before April 2024 also for trucks over 8 t). There are no separate urban or rural statutory limits. Urban and rural limits are set by zoning rather than statute.
Implementation of speed limits in Japan can be summarized as:
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.
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.
There is also a major distinction 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 applied for each.
Although some surface streets such as viaducts, trunk and bypass roads are built to expressway standards, many are not legally classified as expressways and are typically distinguishable by the colour of direction signs: surface streets use blue direction signs while expressways use green signs.
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 any 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 become a controlled-access highway.
A speed limit can be set at maximum 120 km/h (approximately 74.6 mph) on a divided expressway, if it has low crash rates, both the lowest adaptation speed and design speed is 120 km/h and the length is 20 km (12 miles) or more; on an undivided expressway, the speed limit can be set at maximum 70 km/h (43.5 mph).
The speed limit is set with the lowest "structure compatible speed" (構造適合速度, kōzō tekigō sokudo) criteria below, that is based on design speed in some factors. Unlike surface streets, there is no range limit such as ±10 km/h. Therefore, the speed limit can be modified without limit as long as 100 km/h or lower, but the adaptation speed should be "respected".
Intercity expressways typically have higher speed limits, while urban expressways within major cities often have a speed limit of 60 km/h (37.3 mph) and two-lane expressways, typically in rural and remote areas, have 70 km/h (43.5 mph) for simplified division such as guide posts and 80 km/h (49.71 mph) with physical separation.
Most expressways outside of cities have active variable speed limit signs and maximum speeds are lowered according to road conditions such as congestions, accidents, constructions and severe weather. When the statutory speed limits are in effect on national expressways, variable speed limit signs are left blank to indicate that the statutory speed limit applies. Two sets of variable speed limit signs are installed when the regulatory speed limit exceeds the statutory speed limit, which is 100 km/h on national divided expressways or 80 km/h on other roads, to regulate the speed limit for motor vehicles with a trailer and three-wheelers (which always is 80 km/h).
Even some 4-lane expressways have 70 km/h speed limit. There is, however, no speed limit of 90 km/h, although it is allowed.
lane width (3.5 m ≤ : 120 km/h, < 3.5 m : 80 km/h)
shoulder width (1.75 m ≤ : 120 km/h, < 1.75 m : 80 km/h)