Child Seat Law in Japan: Renting a Car with Kids

The rule in one sentence

Under Article 71-3(3) of Japan's Road Traffic Act, a driver must not drive with a child under 6 on board unless that child uses a child restraint (チャイルドシート) that meets Japan's safety standards and suits the child's size. The duty is on the driver, it applies in the front and the back, and it applies to rental cars exactly as to private cars. A violation adds 1 penalty point to the driver's record.

Exemptions: narrow, and rarely relevant to visitors

The law and its Cabinet Order allow a few exceptions. Prefectural police list them as follows:

For a family in a rental car, the practical answer is simple: bring or book a seat for every child under 6.

Which seat for which child

Japan groups child restraints into three broad types. The Ministry of Land, Infrastructure, Transport and Tourism (MLIT) gives these approximate sizes; always follow the label on the seat itself.

JAF explains that an adult seat belt fits properly at about 150 cm; below that height the belt can sit on the neck and stomach. That is why JAF recommends a booster even after the legal age of 6.

Approved seats: R44, R129 and the E mark

A seat used for a child under 6 must meet Japan's safety standards. A seat confirmed to meet them carries an approval label. The National Police Agency and MLIT leaflet shows an "E" mark with a number — E43 is Japan — and states that seats with other numbers are also compliant. In practice:

• UN R44 labels show weight groups (for example 9–18 kg).
• UN R129 (i-Size) labels show a height range. R129 added side-impact tests, chooses seats by height and requires rear-facing travel until at least 15 months. According to JAF Mate, production in Japan moved fully to R129 in September 2023.
• MLIT has warned that seats sold online without the approval mark failed Japanese crash tests. A seat without a label does not meet the requirement, even with the seat belt on.

Bringing your own seat from abroad

Many families fly with their own seat. Before you pack it:

1. Check the label. Look for an orange or white UN approval label with an "E" and a number (R44 or R129). European seats normally carry one.
2. Seats approved only under another country's system — for example a US label that refers to FMVSS 213 without an E mark — are not covered by the marks shown in the Japanese leaflet. If your seat has no E mark, consider requesting a seat from us instead.
3. Check the installation method. A belt-installed "universal" seat works with a three-point belt. An ISOFIX seat needs ISOFIX anchors in the car (see below).
4. Ask your airline how it carries car seats; rules differ by airline.

ISOFIX or seat belt installation

ISOFIX seats clip onto metal anchors at the back of the car's seat base. MLIT explains that some ISOFIX seats are approved only for specific car models, while "universal" ISOFIX seats use a top tether and need a car that is compatible with them — check the seat maker's vehicle list. Belt-installed seats are fixed with the car's three-point belt. Either way, MLIT advises:

• Install the seat in the back seat whenever possible.
• Never put a rear-facing seat in a front seat with an airbag.
• Push the top of a forward-facing seat: it should move no more than about 3 cm.
• In summer, check that buckles and metal parts are not too hot before seating the child.

Child seats with Go on Rent-a-Car

• Request it when you book. In the booking form, tick "I would like a child seat (subject to availability)" and enter the number of passengers. Check availability and book at least 48 hours before pick-up.
• Tell us about your child. Use the "Message (optional)" field for the child's age, height and weight, and how many seats you need. We confirm what we can provide.
• Price. Any charge for a child seat is shown on the site or in our confirmation — please check there; we do not quote it here.
• The car. The Volkswagen Golf Variant TSI Lounge has 5 seats (children count as passengers) and a 605-litre boot (1,620 litres with the rear seats folded), useful for a stroller and suitcases.
• Handover. At Haneda Terminal 3, P5 car park 8F, we check the seat installation with you before you leave. See our Haneda pick-up guide.

Family road-trip tips

• Plan breaks. Expressway service areas (SA) and parking areas (PA) make regular stops easy. Japan's expressway companies have been adding 24-hour baby corners with diaper-changing spaces and nursing rooms at service areas with shops; check each SA on the operators' sites before you go.
• Do the buckles yourself every time, and lock the rear doors with the child lock.
• Never leave a child alone in the car, even for a few minutes.
• Read our guide to Japan's road rules for visitors — everyone must wear a seat belt, front and back — and keep our emergency guide on your phone.