Irish Driving Rules & Road Signs Explained

Driving in Ireland is straightforward once you understand the basics. Yes, we drive on the left—but that's just the beginning. This guide covers everything you need to know about Irish road rules, signs, and the unwritten codes of the road.

The Fundamentals

Driving on the Left

Ireland drives on the left side of the road, with the steering wheel on the right. This takes adjustment if you're used to driving on the right, but most visitors adapt within an hour or two.

Tips for adjusting:

• Your position in the car should be towards the centre of the road
• The gear stick will be on your left (if driving manual)
• Look right first at junctions, then left
• Take your first few junctions slowly
• Roundabouts go clockwise (not counter-clockwise)

Speed Limits

All speed limits in Ireland are in kilometres per hour (km/h):

Important: Speed limit signs are circular with a red border and black numbers. When you enter a new zone, the limit changes immediately.

Road Signs Decoded

Irish road signs follow European conventions, with some uniquely Irish additions.

Warning Signs (Yellow Diamond)

Yellow diamond-shaped signs with diagonal black stripes warn of hazards ahead:

• Curves, junctions, pedestrian crossings
• Livestock crossing areas
• Road works zones

Regulatory Signs (Circular)

• Red circle: Prohibition (no entry, no overtaking)
• Blue circle: Mandatory action (must turn left, minimum speed)
• Speed limits: Red circle with number

Information Signs (Blue Rectangle)

• Direction signs on motorways
• Service area locations
• Tourist attraction pointers (brown background)

Bilingual Signs

Many signs display text in both English and Irish (Gaeilge). On some Western roads, you'll see Irish-only signs. Key words to know:

Road Markings

Centre Lines

• Single broken white line: Overtaking permitted when safe
• Single continuous white line: No overtaking
• Double continuous white lines: Absolutely no overtaking

Edge Markings

• Yellow lines (at kerb): No parking restrictions
  • Single yellow: No parking at certain times
  • Double yellow: No parking at any time
• White hatching: Do not enter this area

Roundabouts

Ireland has an exceptional number of roundabouts—rumour has it we have the highest per-capita in Europe.

The Rules

1. Always give way to traffic already on the roundabout (coming from your right)
2. Travel clockwise around the roundabout
3. Signal left when exiting (after passing the exit before yours)
4. Choose your lane based on your exit:
   • Left lane: First exit (left) or straight
   • Right lane: Later exits or going full circle

Multi-Lane Roundabouts

Larger roundabouts may have 2-3 lanes:

• Left lane: First or second exit
• Middle lane: Straight ahead
• Right lane: Third exit onwards or U-turn

Check out our detailed Roundabout Guide for diagrams and scenarios.

Mandatory Requirements

Seatbelts

All occupants must wear seatbelts. This is strictly enforced.

• Front seats: Always required
• Rear seats: Required for all passengers
• Children under 150cm or 36kg: Appropriate child restraint required

Mobile Phones

Using a hand-held phone while driving is illegal. This includes:

• Making calls
• Texting
• Checking messages
• Any physical interaction with the phone

Hands-free devices are permitted, but pulling over for calls is safest.

Drink Driving

Ireland has strict drink-driving laws:

• Standard limit: 50mg alcohol per 100ml blood
• Professional/learner drivers: 20mg per 100ml blood

The safest approach: don't drink and drive at all.

Northern Ireland Differences

If your road trip includes Northern Ireland routes, note these differences:

• Speed limits are in miles per hour (mph)
• Distance signs are in miles
• Currency changes to pounds sterling
• Otherwise, road rules are virtually identical

There are no border checkpoints—you may not even notice crossing.

Unwritten Rules of Irish Roads

The "Thank You" Wave

When another driver lets you pass on a narrow road, pulls in to give you space, or shows any courtesy, a quick wave or flash of hazard lights is the standard acknowledgment. It's not mandatory, but it's very much expected.

Narrow Road Etiquette

On single-track lanes (common in scenic areas):

• Whoever is closer to a passing place should use it
• If the passing place is on your right, stop opposite it—don't cross to the other side
• Sometimes reversing to a passing place is necessary
• Take your time; rushing leads to scraped mirrors

Flashing Headlights

A quick flash of headlights usually means:

• "I'm letting you go first"
• Warning of a hazard (or speed check) ahead

Context matters—use your judgment.

Emergency Information

Emergency Number

999 or 112 for all emergencies (police, ambulance, fire)

Breakdowns

• Move to a safe location if possible
• Use hazard lights
• Wear a high-visibility vest if leaving the vehicle
• Contact your rental company's breakdown service

Garda (Police)

Irish police are called the Gardaí (singular: Garda). They're generally helpful and approachable if you need assistance.

Before You Drive

Preparation Checklist

• Familiarise yourself with the vehicle's controls
• Adjust mirrors for left-side driving
• Know where lights, wipers, and hazards are
• Download offline maps for your route
• Check weather conditions

Your First Drive

• Start with quieter roads, not motorways
• Give yourself extra time at junctions
• Don't be afraid to pull over and reset if needed
• Most drivers are patient with visitors

Ready for the Road?

With these rules in mind, you're ready to explore Ireland safely. Start with an easier route like the Boyne Valley before tackling challenging drives like Connemara.

For more practical advice, check out our guides on:

• Navigating Irish Roundabouts
• Toll Roads in Ireland
• Best Navigation Apps