The UK drink drive limit is 35 micrograms of alcohol per 100 millilitres of breath, 80 milligrams per 100 millilitres of blood, or 107 milligrams per 100 millilitres of urine in England, Wales, and Northern Ireland. Scotland is stricter: 22 micrograms in breath, 50 milligrams in blood, or 67 milligrams in urine. The limits apply to every driver, full licence or provisional, and no fixed number of drinks will reliably keep you under them.
The Limits in England, Wales, and Northern Ireland
Section 5 of the Road Traffic Act 1988 makes it an offence to drive, attempt to drive, or be in charge of a vehicle on a road or public place with alcohol above the prescribed limit.1Legislation.gov.uk. Road Traffic Act 1988 – Section 5 The three measurements are:
- 35 micrograms of alcohol per 100 millilitres of breath
- 80 milligrams of alcohol per 100 millilitres of blood
- 107 milligrams of alcohol per 100 millilitres of urine
A reading at or below the limit means you have not committed the section 5 offence. You could still be prosecuted under section 4 for driving while unfit through drink if your driving itself shows clear impairment.
The Scottish Limit
Scotland reduced its drink-drive limits in December 2014 using powers devolved through the Scotland Act 2012.2Scottish Government. Drink-Drive Limit: Policy The Scottish figures are:
- 22 micrograms of alcohol per 100 millilitres of breath
- 50 milligrams of alcohol per 100 millilitres of blood
- 67 milligrams of alcohol per 100 millilitres of urine
Someone who might lawfully drive home from a pub in Newcastle could be well over the limit a few miles up the road in Edinburgh. If you drive across the border, the Scottish numbers are the ones that matter.3Legislation.gov.uk. The Road Traffic Act 1988 (Prescribed Limit) (Scotland) Regulations 2014
Why No One Can Tell You How Many Drinks Is Safe
The government’s own guidance states that it is impossible to say how many drinks equate to the legal limit, because the outcome depends on your weight, age, sex, metabolism, what you have eaten, and your stress levels.4GOV.UK. The Drink Drive Limit Two people drinking the same pints at the same pace can give very different breath readings an hour later.
The bigger trap is the morning after. Around 5,500 people fail a breath test the following morning each year, often convinced the alcohol has worn off.5THINK! Morning After Alcohol leaves the body at a roughly fixed rate, and sleep does not speed it up. A heavy session ending at midnight can leave you over the limit at eight the next morning. Coffee and a shower change nothing.
How the Police Test You
Testing happens in two stages. The first is at the roadside, the second at a police station.
At the Roadside
A uniformed officer can require a preliminary breath test if they reasonably suspect you have alcohol in your body, if you have committed a moving traffic offence, or if you were involved in an accident.6Legislation.gov.uk. Road Traffic Act 1988 – Section 6 This is a screening test only; it decides whether a formal evidential test is justified. Refusing the roadside test without a reasonable excuse is itself a criminal offence.
At the Station
If the roadside screen is positive, you will be taken to a station and asked for two specimens of breath on an approved evidential machine.7Legislation.gov.uk. Road Traffic Act 1988 – Section 7 The higher of the two readings is discarded, and the lower one becomes the evidence against you. Police can take a blood or urine sample instead where there is a medical reason you cannot blow, or where the breath machine is unavailable or unreliable.
Penalties if You’re Over the Limit
The sentence depends heavily on what you did. A simple over-the-limit offence sits at the bottom of the scale; causing death sits at the top.
Driving or Attempting to Drive
The maximum penalty is six months in prison, an unlimited fine, or both, plus a minimum 12-month disqualification.8Sentencing Council. Drink Driving If you have a drink-driving or related conviction in the past ten years, the minimum ban rises to three years.9Legislation.gov.uk. Road Traffic Offenders Act 1988 – Section 34
Causing Death
If someone dies as a result of your careless driving while over the limit, the maximum sentence is life imprisonment for offences committed after 28 June 2022. The minimum ban is five years with a compulsory extended re-test, rising to six years for a repeat offender. Sentencing starting points run from 18 months to 12 years depending on alcohol level and the standard of driving.10Sentencing Council. Causing Death by Careless Driving Whilst Under the Influence of Drink or Drugs
Refusing to Provide a Sample
Refusing a breath, blood, or urine sample without a reasonable excuse is treated as seriously as the drink-driving offence itself. If you were driving or attempting to drive, you face up to six months in prison, an unlimited fine, and a minimum 12-month ban.7Legislation.gov.uk. Road Traffic Act 1988 – Section 7 The officer must warn you that a refusal can lead to prosecution. Saying you “couldn’t blow hard enough” without medical evidence rarely works as a defence.
High Risk Offenders
The DVLA treats some drivers as high risk offenders, which puts an extra barrier between you and your returned licence. You fall into this group if you were convicted of two drink-driving offences within ten years, if your breath reading was 87.5 micrograms or more (or the blood or urine equivalent), or if you refused to provide a sample.11GOV.UK. Driving Disqualifications – Disqualification for Drink-Driving
At the end of your ban, you will not get your licence back until you pass a medical examination with a DVLA-appointed doctor, who checks for an ongoing alcohol problem. This can add months to the time before you can actually drive again.
The Rehabilitation Course
Courts can offer a place on an approved drink-drive rehabilitation course when they hand down the ban. Completing the course cuts your disqualification by up to a quarter, with a minimum reduction of three months, so a standard 12-month ban comes down to nine.12Sentencing Council. Reduced Period of Disqualification for Completion of Rehabilitation Course The court is not obliged to offer it, and you pay the fee yourself. If it is offered and you can afford it, taking it is usually worth it for the shorter ban alone.
Life After the Conviction
Your Licence Record
A drink-driving conviction leaves a DR10 endorsement on your licence that stays visible for 11 years from the date of conviction. For the first ten of those years, a court can use it to enhance the sentence for any new offence.13GOV.UK. Penalty Points (Endorsements) – How Long Endorsements Stay on Your Driving Record
Insurance
A DR10 hits car insurance hard. Many mainstream insurers will not quote at all, pushing you onto specialist convicted-driver policies at much higher premiums. The extra cost tends to be worst in the first five years, while the endorsement is still fresh on your record.
Travelling Abroad
A drink-driving conviction is a criminal record, and that can affect foreign travel. The United States is the most commonly cited example: a criminal conviction generally rules out the Visa Waiver Programme, so you would need to apply for a full visa through the American Embassy before visiting. Other countries have similar restrictions. One conviction can create years of extra paperwork for anyone who travels regularly.