Guides/Theory test

Drink Driving Limit Ireland: 50mg, 20mg for Learners, Fines and Bans

Updated 6 October 2026 · 5 min read

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The drink driving limit in Ireland is 50mg of alcohol per 100ml of blood for a driver who has held a full licence for more than two years. For learner permit holders, drivers in their first two years on a full licence and professional drivers (bus, truck, taxi and other public service vehicles) the limit is 20mg per 100ml of blood. In breath the two limits are 22µg and 9µg per 100ml, in urine 67mg and 27mg.

Those numbers come from Section 4 of the Road Traffic Act 2010. Every conviction carries a disqualification, there is no fine-only outcome, and 20mg is close to zero in practice. One drink can put a learner over it.

Which limit applies to a learner permit holder?

The 20mg limit. The law treats anyone on a learner permit, anyone with no valid licence or permit, and anyone who has held a full licence for two years or less as a "specified person", and the lower limits apply to all of them. So if you pass the theory test this winter and pick up your first learner permit in 2027, you drive under the 20mg limit for the whole of the permit and for the first two years of the full licence after it.

The same lower limit applies to drivers of buses, lorries, trailers, work vehicles and taxis, however long they have held the licence.

What is the fine for a first drink driving offence?

Below a certain level you get a fixed penalty notice instead of a court date, provided you held a valid licence or permit at the time and have not had a similar notice in the previous three years. Pay the fine within 28 days and the disqualification on the notice applies without a court appearance.

Until 2018 the lowest band for experienced drivers carried three penalty points rather than a ban. The Road Traffic (Amendment) Act 2018 replaced the points with a three-month disqualification, which is why the theory test answer for the 50mg to 80mg band is now a ban and not points.

What happens above the fixed penalty range?

Above 100mg for an experienced driver, or above 80mg for a learner, novice or professional driver, there is no fixed penalty. The Garda summonses you to the District Court. The same happens if you do not pay a fixed penalty notice in time, or if you had one in the last three years. The disqualification periods below are minimums and the judge can increase them.

The maximum penalty for drink driving alone is a €5,000 fine or six months in prison, or both. Refusing to give a breath, blood or urine sample is a separate offence. A ban of more than two years can be shortened by the District Court once you are past the halfway point, for a €55 fee, unless you had another disqualification in the past ten years.

How is the limit tested on the road?

Gardaí must breath test a driver they believe has taken alcohol, and every driver at a collision where someone needs medical attention. The roadside device gives a pass or fail. A failed test means a trip to the station for an evidential breath, blood or urine sample, and that reading decides which band you fall into. The limit applies for three hours after driving, and morning checks are routine.

Which theory test questions cover drink driving?

• Question 777: penalties for a learner at 20mg to 80mg (€200 fine and a 3-month disqualification).
• Question 778: the same band for a professional driver on a full car licence.
• Question 779: penalties for a driver at 80mg to 100mg (€400 fine and 6 months).
• Question 580: what one unit of alcohol can cost a learner driver (a 3-month disqualification).
• Questions 221 and 222: how alcohol affects judgement, concentration and reaction time.