From 1 September 2026, the default limit on Japanese roads without a centre line is 30 km/h

What a "statutory" limit is, and why only that number moves

Japanese speed limits come in two kinds. A posted limit (指定速度) is the number on a sign or painted on the road. A statutory limit (法定速度) is the default that applies when there is no sign at all. The 2026 amendment changes only the second kind. No posted limit changes, and no sign is being replaced.

That is why the change is easy to miss and easy to get caught by: the roads affected are precisely the ones with nothing written on them.

Source National Police Agency — “The statutory speed limit for cars on residential roads is being lowered” (in Japanese) · Tokyo Metropolitan Police Department — “The statutory speed limit on residential roads” (in Japanese)

How to tell, from the driver’s seat, which limit applies

The National Police Agency describes a 生活道路 as "a road used mainly for the daily life of local residents, with no centre line or similar marking". That phrase is a description, not the legal test — the word 生活道路 does not appear in the statute at all.

What the amended Article 11 of the Enforcement Order actually does is list four kinds of ordinary road that keep 60 km/h, and then set every other ordinary road at 30 km/h. A residential road is the leftover category. So the reliable way to read a street is to check whether it is on the list.

The four kinds of road that stay at 60 km/h

• An ordinary road with a centre line or designated lane markings, whether by sign or by road marking
• An ordinary road where the two directions of travel are physically separated — by the structure of the road, or by fences or similar installations specified in Cabinet Office regulations
• The parts of a national expressway other than the main carriageway and its acceleration and deceleration lanes
• A motor-vehicle-only road (自動車専用道路)

The last two concern expressways. In town, the decision reduces to two questions, in order. Is there a centre line or lane marking painted on the surface? If not, are the directions divided by a median, a fence, bollards or similar? If the answer to both is no, the limit on that street is 30 km/h from 1 September 2026.

The scope of "similar installations" is defined in Article 5-6-3 of the Enforcement Regulations: fences, wheel stops, post-shaped installations and other installations placed so that a car cannot pass to the right of them. A street divided by a line of bollards therefore keeps 60 km/h even with no paint on the road.

Source National Police Agency — “The statutory speed limit for cars on residential roads is being lowered” (in Japanese)

A posted sign always wins — in both directions

A statutory limit is only the fallback. Where a limit is posted, the posted number is the maximum speed. This cuts both ways, and the National Police Agency spells out both cases:

• Statutory limit 60 km/h, sign posts 30 km/h → the maximum speed is 30 km/h
• Statutory limit 30 km/h, sign posts 40 km/h → the maximum speed is 40 km/h

The second line is the one that becomes newly relevant. After 1 September 2026 a street with no centre line has a statutory limit of 30 km/h — but if a 40 sign is posted on it, 40 is the limit. "No centre line means 30" is a false generalisation, and it is exactly the shape of statement a true/false question is built from.

Source National Police Agency — “The statutory speed limit for cars on residential roads is being lowered” (in Japanese) · Tokyo Metropolitan Police Department — “The statutory speed limit on residential roads” (in Japanese)

If you are driving on an international permit right now

Two things follow from this being a change to the road rules rather than to licensing. Take them in that order, because only the first is something the police pages state.

First, mopeds are unaffected. The amended Article 11 sets the maximum for a moped on any ordinary road at 30 km/h regardless of road category, which is what it already said. From September, cars and mopeds share the same 30 km/h default on a street with no centre line.

Source National Police Agency — “The statutory speed limit for cars on residential roads is being lowered” (in Japanese)

Second — and this is reasoning from the scope of the amendment, not something the sources above say about licenses — a speed limit binds the driver of a vehicle on a road, and nothing in the amended Article 11 is conditioned on which license that driver holds. So from 1 September 2026 the new default should be expected to apply to a visitor driving on an international driving permit and to a resident driving on a foreign license with a certified Japanese translation, exactly as it does to the holder of a Japanese license. If you need that confirmed for your own situation, the prefectural police where you are living are the body to ask.

What this means for the license-conversion written test

The knowledge confirmation tests the traffic rules as they stand on the day you sit it. Take it before 1 September 2026 and 60 km/h is the correct answer for an unmarked road; take it after, and 30 km/h is. Study material is not guaranteed to be updated on the day a rule changes, so check the date on anything you revise from — and check that it says which side of 1 September 2026 it is describing.

Since 1 October 2025 the knowledge confirmation is 50 questions with 45 correct required to pass, which is 90 per cent. Dropping one speed question to an out-of-date number takes your margin from five wrong answers to four.

Source Tokyo Metropolitan Police Department — “Amended Road Traffic Act Enforcement Regulations, in force 1 October 2025” (in Japanese)

Speed questions reward knowing the order of decision — sign first, then road category — more than memorising figures. Five practice questions on it:

Speed and Following Distance — 5 practice questions

Both the National Police Agency and the Tokyo Metropolitan Police add the same advice alongside the change: staying inside the posted or statutory limit is a floor, not a standard, and the speed you should actually drive depends on the road, the traffic, the weather and how far you can see. The streets dropping to 30 km/h are the ones where the people who live there walk and cycle.

Source National Police Agency — “The statutory speed limit for cars on residential roads is being lowered” (in Japanese) · Tokyo Metropolitan Police Department — “The statutory speed limit on residential roads” (in Japanese)