It's the same limit as a car — but the fallout isn't
I'll say this straight: the drink drive limit for an HGV driver is the same as for a car driver. In England, Wales and Northern Ireland, 35 micrograms of alcohol per 100ml of breath. 80 milligrams per 100ml of blood. 107 milligrams per 100ml of urine. There's no stricter statutory threshold just because you're driving a 44-tonne artic.
But that's where the similarity ends. Because what happens to a car driver after a conviction and what happens to an HGV driver after the same conviction are two completely different situations — and most drivers I know who've thought about this haven't thought through the second part.
This post is about what actually follows a drink drive conviction when your income depends on your Group 2 licence.
The limit, and what it means at the roadside
England, Wales and Northern Ireland: 35µg per 100ml of breath. 80mg per 100ml of blood. 107mg per 100ml of urine. Scotland is lower: 22µg per breath, 50mg per blood, 67mg per urine — the lower Scottish limit has been in force since December 2014. If you cross the border regularly, that's relevant.
At the roadside, a police officer uses a hand-held screening device first — a Breathalyser or similar approved instrument. If that shows positive, you go back to the station for an evidential test on an approved breathalyser. The evidential reading is what gets used in any prosecution. Below 40µg on the evidential reading, and the station has discretion to offer a blood or urine test instead, which sometimes results in a lower reading — but that's at the officer's discretion, not something you're entitled to demand.
The important thing to understand: you don't have to be visibly impaired to be over the limit. The offence under the Road Traffic Act 1988 (Section 5) is exceeding the prescribed limit, full stop. Impairment is a separate offence under Section 4. You can be over the limit and appear entirely composed at the roadside and still be guilty under Section 5.
What a first conviction actually costs
Magistrates' court for a Section 5 drink drive offence: minimum 12-month disqualification. That's the statutory floor. In practice, first-time offenders with a reading just over the limit tend to get somewhere between 12 and 18 months. Higher readings, or any aggravating factors — driving erratically, an accident, a passenger — push the ban longer and can add an unlimited fine or a community order.
There's a drink drive rehabilitation course you can complete to reduce the ban by up to a quarter. Costs around £150–£250 depending on the provider. For a 12-month ban you'd serve 9 months, which sounds better — but 9 months without a licence is still 9 months.
For a car driver doing office work, a 12-month ban is genuinely serious. You might lose a job, you'll definitely have higher insurance costs for several years, and the conviction shows on your licence for 11 years.
For an HGV driver, those same numbers are a different problem entirely.
Your Group 2 licence during and after a ban
A drink drive disqualification removes your entitlement to drive any category on your licence. That means Cat C, Cat C+E — all of it, for the duration of the ban. You can't work as a professional driver. Your income stops unless you've got something to fall back on.
When the ban ends, you don't automatically get the Group 2 entitlement back. DVLA requires a medical assessment before reinstating an LGV licence after a drink drive conviction. That's a D4 medical — full Group 2 standard examination — and depending on the circumstances, DVLA may require a period of abstinence to be demonstrated before they'll issue. For a single conviction at low-range levels, that's usually manageable. For someone with a pattern of drink-related issues, DVLA has broader discretion.
The medical costs money and takes time. DVLA processing adds more time. A 12-month ban might effectively mean 14–16 months off the road before you're back behind the wheel of an HGV professionally.
The operator licence problem
Here's the bit that catches drivers by surprise. Say you're an owner-driver with your own O-licence. A drink drive conviction goes on your licence — and your licence is the basis of your operator licence application. The Traffic Commissioner has discretion to review an operator's fitness to hold a licence when there's a relevant conviction on record.
The most common outcome for a sole trader with an O-licence and a drink drive conviction isn't an immediate revocation — it's a call-up letter, followed in some cases by a short-form public inquiry. Not every TC takes the same approach, and a single conviction at the lower end, properly explained, is often managed without losing the licence. But the inquiry itself costs time and money, and the outcome isn't guaranteed.
I know a driver who ran a four-vehicle fleet out of Coventry. One drink drive conviction — morning after a work event, thought he was fine, wasn't. The magistrates gave him 14 months. The TC called him in. He kept his licence but got a formal warning on record and a six-month review period. The insurance for the fleet that year went up by an amount that hurt.
Agency drivers and operator sanctions
If you're working agency, you don't have your own O-licence — but your conviction will still show on your licence when the agency's operator checks it. Employers are entitled to carry out DVLA licence checks, and most transport agencies and operators do so at induction and at intervals during employment.
A drink drive conviction on a professional driver's licence is a very significant flag. Most operators have a standing policy that any drink drive conviction results in immediate removal from driving duties. Some agencies' contracts make this an automatic termination. Even if your employer doesn't make it explicit, insurers often do — they won't cover a driver with a recent drink drive conviction on a goods vehicle policy.
So you can serve your 9 or 12 month ban, get the medical, get the licence back, and still struggle to get work through the normal agency route for several years — because operators are commercially exposed when they put you on a vehicle and their insurer finds out.
Scotland: the lower limit matters more than you might think
The 22µg limit in Scotland is about 63% of the England/Wales limit. The practical difference: a couple of pints of standard strength beer the evening before a 4am start might put you inside the English limit but over the Scottish one. Metabolisation rate varies by individual — weight, hydration, time elapsed — but the Scottish limit leaves substantially less margin.
If you're running regular trunk work on the M74, A74(M) or A1 into Scotland — Carlisle across the border, Glasgow, Edinburgh — the relevant limit at the roadside is the Scottish one from the moment you cross. Most of the drivers I know who run that corridor are aware of this. The ones who aren't are usually the ones who treat a trip to Scotland as just another long run and forget the legal context changes at the border.
Morning-after: the calculation most drivers get wrong
The most common reason professional HGV drivers get caught drink-driving isn't an evening session before an early morning run. It's an assumption that a night's sleep has cleared the alcohol when it hasn't.
Alcohol clears the body at roughly one unit per hour on average. That rate varies — it's slower if you're tired, if you drank on an empty stomach, if you're older. There's no reliable shortcut: not coffee, not cold showers, not food. The only thing that removes alcohol from your system is time.
If you had four pints (roughly eight units) from 7pm to 11pm, finished around midnight, and your cab alarm goes off at 5am — that's seven hours. Rough arithmetic: about 7 units cleared, leaving one unit in the system. One unit might put you at 15-20µg on a breath test. Probably under the English limit. Certainly not under the Scottish one. And that rough arithmetic could be significantly out if you're tired, if you drank faster than you remember, or if you had wine or spirits rather than pints.
This isn't a lecture. It's arithmetic. The numbers matter because the career consequence of getting them wrong is very different for you than it is for someone driving to work in a company car.
The employer zero-tolerance that exists in most contracts
Aside from the legal limit, most large operators and most transport agencies have an internal zero-tolerance alcohol policy for drivers reporting for duty. This is a contractual obligation, not a legal standard. It means that an employer can legitimately remove you from duties if they believe you're impaired by alcohol — even if a breath test would show you under the legal limit.
Roadside drug and alcohol testing — already covered on this site in the context of the DrugWipe process — can include breath testing of vehicle crews. A positive at the roadside or a positive on return to depot is a contractual matter separate from the criminal offence, and the outcomes can overlap: criminal conviction plus contractual dismissal are both possible from the same incident.
The headline number — 35µg — is what the law enforces. But for most HGV employment, the operational standard is lower than that, even when it isn't written down in so many words.
If you're stopped
You're legally required to provide a specimen of breath when required by a police officer who has reasonable cause. Failing without reasonable excuse is itself an offence — and the penalty for failing to provide can be the same as for drink driving itself. There's no tactical advantage to refusing.
If you're charged, get proper legal representation before the magistrates' court appearance. The sentencing guidelines have ranges, and the specific reading, your circumstances, and any mitigating factors are all in play. Representing yourself on a drink drive charge when your professional licence is at stake isn't something I'd recommend to anyone.
If you work agency or for an operator, tell your employer promptly. Getting caught is one thing — attempting to conceal a conviction from an employer who carries out licence checks creates a separate employment law problem on top of the conviction itself.