Ireland vs Japan: Driving Rules Compared

Ireland lets you run the motorway at 120 km/h; in Japan the ceiling is 100 km/h. Alcohol limits differ too (0.05 vs 0.03), and the table below lines the rest up rule by rule.

Both Ireland and Japan drive on the left side of the road. If you are used to left-hand traffic, the transition is seamless.

Speed Limits Comparison

Speed limits differ between Ireland and Japan, and understanding these differences is essential for avoiding fines.

Drivers in Ireland should observe limits of 50 km/h in built-up areas, 80 km/h on rural roads, and 120 km/h on motorway stretches.

In Japan, the standard speed limits are 40 km/h in urban areas, 60 km/h on rural roads, and 100 km/h (100 km/h standard; 120 km/h on select expressway sections (Shin-Tomei, Tohoku, Joban). From Sept 2026, narrow residential roads default to 30 km/h) on motorways.

Key Speed Limit Differences

Drivers transitioning between Ireland and Japan should pay close attention to posted signs, as assumptions based on one country’s rules can lead to speeding tickets in the other. Speed cameras are common in both countries, and enforcement can be strict.

Traffic Rules and Regulations

Beyond speed limits, Ireland and Japan have several important differences in their general traffic rules.

Driving side: Ireland drives on the left; Japan drives on the left. Since both countries use the same driving side, the transition is seamless in this regard.

Minimum driving age: The minimum age to drive a car is 17 in Ireland and 18 in Japan.

Mobile phone use: Using a handheld mobile phone while driving is illegal in both countries. In Ireland, the penalty is EUR 60 + 3 penalty points. In Japan, the penalty is JPY 18,000 (approx. EUR 115) + 3 points. Hands-free devices are generally permitted in both countries, but drivers should keep their attention on the road.

Seatbelts: Seatbelts are mandatory for all occupants in both Ireland and Japan. The fine for not wearing a seatbelt is EUR 60 + 3 penalty points in Ireland and Warning / 1 point (no fine for first offence) in Japan.

Running a red light: Red-light violations carry serious penalties. In Ireland, expect EUR 80 + 3 penalty points. In Japan, the penalty is JPY 9,000 (approx. EUR 55) + 2 points.

Alcohol and DUI Laws

Drink-driving laws represent one of the areas where countries diverge most significantly.

Ireland sets its blood alcohol concentration (BAC) limit at 0.05%.

Japan has a BAC limit of 0.03%.

The lower limit in Japan means that even a small amount of alcohol could put you over the legal limit. Adjust your behaviour accordingly.

In both countries, penalties for drink-driving include fines, licence suspension, and potential imprisonment for serious offences. New and young drivers often face stricter limits (typically 0.00% to 0.02% BAC) in both Ireland and Japan. The safest approach is always to avoid any alcohol before driving.

Tyre and Equipment Requirements

Tyre regulations and mandatory vehicle equipment differ between Ireland and Japan, and non-compliance can result in fines, especially during winter.

Winter Tyres

• Ireland: Winter tyres are not mandatory. Studded tyres: allowed. Minimum tread depth: 1.6 mm.
• Japan: Winter tyres are situational. Period: Prefectural regulations; Hokkaido, Tohoku require winter tyres in winter. Studded tyres: restricted. Minimum tread depth: 1.6 mm.

Mandatory Equipment

Rental vehicles usually come equipped for the country of hire. If you intend to drive in both Ireland and Japan, check with the rental company that the vehicle has all required items for both destinations.

Speeding Penalties

The financial consequences of speeding vary between Ireland and Japan.

In Ireland, a minor speeding offence (approximately 10 km/h over the limit) typically results in: EUR 80 (fixed charge) + 3 penalty points. Penalties escalate significantly for higher speeds, and repeat offenders face licence suspension.

In Japan, a minor speeding offence (approximately 10 km/h over the limit) typically results in: JPY 9,000 (approx. EUR 55) + 1 point. Penalties escalate significantly for higher speeds, and repeat offenders face licence suspension.

Both countries use a combination of fixed speed cameras, mobile speed traps, and in some cases average speed (section control) cameras.

Licence Requirements for Visitors

Licence requirements for foreign visitors differ between {a} and {b}. Here is what you need to know.

Ireland: An EU/EEA driving licence is valid. An IDP is recommended for non-EU licence holders. Visitors can typically drive for up to 12 months on a foreign licence EU/EEA and UK licences valid. IDP recommended for non-EU visitors.

Japan: An IDP is required. Visitors can typically drive for up to 12 months on a foreign licence IDP required (1949 Geneva Convention only). US, UK and many EU licences need specific IDP. Drives on the left.

Always carry your licence (and IDP if applicable) while driving, as police may request to see it during routine checks or traffic stops.

Emergency Numbers

Save these emergency numbers before travelling to Ireland or Japan:

Save these numbers in your phone before travelling. In an emergency, quick access to the correct number is crucial.

Practical Tips for Driving in Both Countries

If you are planning to drive in both Ireland and Japan, here are some practical tips to keep in mind:

1. Research before you go. Familiarise yourself with the specific rules of each country before your trip. Print or save a summary of key rules for quick reference.

2. Learn key phrases. If you do not speak the local language, learn basic driving-related phrases. In an emergency, being able to communicate with police or paramedics can be invaluable.

3. Use a GPS or navigation app. Modern navigation apps often include speed limit warnings, toll information, and real-time traffic updates that can help you comply with local rules.

4. Adjust to speed limits immediately. When crossing the border, speed limits change. Look for signs and adjust your driving accordingly. Do not rely on habits from the other country.

5. Check insurance coverage. Verify that your motor insurance or rental agreement covers driving in both countries. A Green Card may be required for cross-border travel.

6. Equip your vehicle properly. Ensure you have all mandatory equipment for both countries. It is better to carry extra items than to face a fine for missing equipment.

7. Understand toll systems. Research whether you need a vignette, transponder, or cash for tolls in each country.

8. Carry the right documents. Ensure you have your driving licence, IDP (if needed), vehicle registration, and insurance documents. Some countries require you to carry these at all times.

Which Country Is Easier for Tourists to Drive In?

Tourist-friendliness of driving varies between Ireland and Japan based on several factors.

Tourist reviews give Ireland a driving ease score of 2.6/5 (Easy). Left-hand driving, narrow rural roads, roundabouts everywhere

Tourist reviews give Japan a driving ease score of 3.0/5 (Moderate). Left-hand driving, expensive tolls, excellent roads, kanji signage

Since both Ireland and Japan drive on the left, the transition between the two is smooth for most drivers.

Frequently Asked Questions

Can I drive in Japan with a Ireland driving licence?

Rules vary by nationality. Check the specific licence requirements for each country, and consider obtaining an International Driving Permit (IDP) before your trip.

What is the speed limit on motorways in Ireland compared to Japan?

The motorway speed limit in Ireland is 120 km/h, while in Japan it is 100 km/h (100 km/h standard; 120 km/h on select expressway sections (Shin-Tomei, Tohoku, Joban). From Sept 2026, narrow residential roads default to 30 km/h). Always watch for posted signs, as limits may vary on specific sections due to roadworks, weather, or local restrictions.

Are winter tyres mandatory in Ireland or Japan?

In Ireland, winter tyres are not mandatory (no specific period). In Japan, they are situational (Prefectural regulations; Hokkaido, Tohoku require winter tyres in winter). If you are travelling during winter months, it is advisable to use winter tyres regardless of legal requirements for safety.

Which country has stricter drink-driving laws?

Japan has a stricter BAC limit (0.03%) compared to Ireland (0.05%). Lower limits mean less alcohol is tolerated before driving becomes illegal.

What side of the road do they drive on in Ireland and Japan?

Ireland drives on the left side and Japan drives on the left side of the road.

Can I use my car insurance from Ireland in Japan?

International motor insurance coverage varies by provider and policy. Contact your insurer before travelling to confirm coverage in both Ireland and Japan. You may need to purchase additional local insurance.

What emergency number should I call while driving in Ireland or Japan?

In Ireland, the general emergency number is 112 (police: 112, ambulance: 112). In Japan, call 110 (police: 110, ambulance: 119). Save both numbers in your phone before you travel.