Japan’s expressway operators and road bureaus publish short, plain-language pages about winter tyres, and they are a better starting point than forum threads. This guide sets out what three primary pages say about which tyres count as winter tyres, what the markings are, and what the two kinds of snow regulation require. It then covers what that means if you are thinking about a second set of wheels for a car in Japan. The translations are ours and we paraphrase rather than quote at length. We read the pages in October 2026; the operators can change their wording at any time.
The Short Version
- Two markings are named. NEXCO West says winter tyres (studless or snow tyres) carry the letters STUDLESS or SNOW on the sidewall, and describes a snowflake mark as the international marking.
- “All wheels” is the wording. NEXCO West asks for winter tyres on every wheel, not on the driven axle only. A Ministry of Land, Infrastructure, Transport and Tourism (MLIT) regional-bureau leaflet uses the same phrase.
- All-season tyres are treated conditionally. NEXCO West asks that an all-season tyre carry the snowflake mark. The MLIT leaflet describes all-season tyres as designed for light, flurry-type snowfall.
- There are two kinds of regulation. A winter-tyre regulation lets through vehicles with winter tyres or anti-slip devices such as chains. In exceptional heavy snow a chain regulation can require chains even on cars with winter tyres on every wheel.
- Wear has a stated limit. The MLIT leaflet says a winter tyre is no longer usable as one once the remaining tread reaches the “platform” step, which it describes as sitting at half the groove depth on a new tyre.
What the Three Sources Are
| Source | Issuer | What we used it for |
|---|---|---|
| Winter tyre page | NEXCO West Japan (expressway operator) | Markings, “all wheels”, all-season tyres, the two regulation types |
| Press release of 4 February 2026 | NEXCO Central Japan | Definition of “winter tyre” used in a fitting-rate survey, the legal duty to use anti-slip measures, survey figures |
| Press release of 28 February 2025 | NEXCO Central Japan | Statement on ordinary tyres on snowy roads |
| Winter-driving leaflet (PDF) | MLIT Hokuriku Regional Development Bureau, Toyama office, with the Toyama transport branch | Platform wear limit, all-season tyres, “all wheels”; the page we read states no date |
NEXCO operates expressways, and the leaflet is aimed at freight operators and large-vehicle drivers, so none of these pages is a general statute. They are the operators’ and bureaus’ own statements of what they expect on their roads.
The Markings the Sources Name
| Marking | Called | What the sources say |
|---|---|---|
| STUDLESS or SNOW lettering on the sidewall | Domestic marking | NEXCO West says winter tyres (studless and snow tyres) have one of these on the sidewall, and asks for tyres with the studless marking on all wheels. |
| Snowflake mark | International marking | NEXCO West asks that all-season tyres carry it. NEXCO Central’s 2026 survey release defines “winter tyre” as a studless or similar tyre bearing the snowflake mark. |
| All-season tyre without the snowflake mark | — | The NEXCO West page names only snowflake-marked all-season tyres as acceptable. It does not discuss an unmarked all-season tyre. |
The NEXCO West page does not mention the “M+S” marking, tread depth or four-wheel drive, so we say nothing about them here.
Winter-Tyre Regulation and Chain Regulation
NEXCO West separates two situations. Under a winter-tyre regulation, a vehicle with neither winter tyres nor an anti-slip device such as tyre chains may not drive the regulated section. The page adds that the device required differs by prefecture. Under a chain regulation, used in exceptional snowfall such as when a heavy-snow special warning or emergency announcement is issued, chains are required even if every wheel carries a winter tyre. The page also tells drivers to carry tyre chains in winter in any case.
NEXCO Central adds two statements. Its 2026 release says prefectural traffic regulations require drivers to take anti-slip measures on snow-covered roads (Okinawa is excluded). Its 2025 release goes further and says that driving on snowy roads with ordinary tyres is a legal violation. We report both as the operator’s wording, not as our reading of the underlying ordinances.
Tread Wear: The Platform
The MLIT leaflet tells drivers to check, using the “platform”, that at least 50% of the groove depth remains. It describes the platform as a step inside the groove that sits at half the height on a new tyre, and says that once wear reaches it the tyre can no longer be used as a winter tyre. This is a wear limit for winter performance. It is a different thing from the legal minimum tread depth for any tyre, which none of these pages states.
Survey Figures, With Their Limits
The February 2026 NEXCO Central release reports winter-tyre fitting rates of 95% for large vehicles and 86% for small vehicles. The release is titled as a second survey of the Tomei (E1) and Chuo (E20) expressways. We did not find the survey dates, sites or sample size in what we read, so the figures should be read as the operator’s headline numbers, not as a national rate.
What This Means When Shopping
If “all wheels” is the standard, a car that will see regulated snow needs four winter tyres. A car can get them by changing tyres on its existing wheels each season, or by keeping a second set of wheels already fitted. That second step is our observation about practice, not a statement from the sources. If you are weighing a second set, the wheel-side questions are the ordinary ones: the bolt pattern, the hub bore and the load rating. Our references on which JDM cars changed bolt pattern and when, on hub bore and on chassis codes that came with two bolt patterns cover the first two. If a car has a Japanese-market spec you are unsure of, ask for the wheel’s printed size and PCD rather than relying on the model name.
What We Could Not Verify
- The legal minimum tread depth for ordinary tyres, which none of the pages we read states.
- Whether the M+S marking is accepted for any regulation. The NEXCO West page does not mention it.
- The ordinance text behind NEXCO Central’s statements. We report the operator’s description only.
- Which anti-slip device each prefecture requires. NEXCO West says it varies.
- The date of the MLIT leaflet, which the page does not state, and whether it is current.
- The method and sample of the Tomei and Chuo fitting-rate survey.
- Whether a given winter-tyre size suits a given wheel width or load rating. Those depend on the tyre maker’s data for the specific tyre, and we did not consult it.
- Any rules outside Japan, and how the expressway operators’ expectations apply to a foreign-registered or imported car.
Looking for a specific set? We specialise in genuine Japanese wheels — RAYS, Volk, Enkei, SSR, WORK, BBS Japan and the rare discontinued sets that never left the country. Tell us the wheel, the fitment, the year — our team searches our networks until we find it.