CBD and Driving in the UK: Is It Legal? Roadside Tests and THC Limits

Is it legal to drive on CBD in the UK?

Yes. UK drug-driving law sets blood limits for a list of named drugs, and THC (delta-9-tetrahydrocannabinol, the part of cannabis that makes people high) is on that list. CBD (cannabidiol) is not. The Home Office says pure CBD, as an isolated substance, is not controlled under the Misuse of Drugs Act 1971.

If you drive, choose a broad spectrum oil whose batch lab report shows THC not detected, and check the report matches your bottle. Our guide to the best CBD oil in the UK explains what to look for on a lab report.

So CBD itself is not the problem. Two things can still get you into trouble: THC in the product you took, and feeling unfit to drive.

The 2 microgram limit applies in England and Wales and, since 2019, in Scotland. Northern Ireland has no set limit; its law is based on whether your driving is impaired. For the wider legal picture, see is CBD legal in the UK? and CBD vs THC.

The two drug-driving offences

Two sections of the Road Traffic Act 1988 matter if you use CBD:

• Section 5A: over the specified limit. It is an offence to drive, or be in charge of a vehicle, with a specified controlled drug in your blood or urine above its limit. For THC that limit is 2 micrograms per litre of blood. It applies even if your driving seems fine.
• Section 4: unfit to drive through drink or drugs. The law treats you as unfit if your ability to drive properly is impaired. This covers any drug, legal or not, including over-the-counter products and prescribed medicines.

CBD is not a specified drug, so section 5A only becomes a risk if your product contains THC. Section 4 applies to everyone, whatever they have taken.

Does a roadside drug test detect CBD?

No. According to GOV.UK, police can use a roadside kit to screen for cannabis and cocaine, and in Northern Ireland the same check is a saliva test. These kits look for THC, not CBD. Police can also ask you to do a field impairment assessment, such as walking in a straight line.

Researchers have tested this directly. In a 2021 trial, 17 healthy adults took pure CBD by mouth at 15mg, 300mg or 1,500mg, then gave saliva samples on two common roadside devices, the Securetec DrugWipe 5S and the Dräger DrugTest 5000. Across more than 500 tests, none came back positive for THC, and no THC was detected in any sample.

So the kit reacts to THC. If your product contains THC, the kit can pick it up even though the label says CBD. Our guide to CBD and drug tests covers workplace and sport tests too.

Why some CBD products contain THC

CBD comes from the cannabis plant, and THC comes from the same plant. The Home Office says it is nearly impossible to extract and isolate CBD without traces of other controlled cannabinoids, such as THC. How much is left depends on how the product is made and how carefully it is tested.

Labels are not always accurate. When UK researchers analysed 29 widely available CBD products, only 11 (38%) were within 10% of the CBD content on the label, and 55% had measurable levels of THC or cannabinol, another controlled cannabinoid. Lab testing by a reputable seller is the only way to know what is in the bottle.

The main risks for drivers are:

• Full spectrum oils, which keep THC on purpose. See what is full spectrum CBD?
• Untested imports and online marketplace products, including some gummies and vapes, where nobody may have checked the THC content.
• THC-like products, such as delta-8 THC, which are not CBD food supplements at all.

There are UK rules on this too. The FSA sets a safe upper limit of 70 micrograms of THC a day and encourages CBD businesses to keep products at or below it. To be sold legally, a CBD product must also meet the Home Office “exempt product” rules, which include no part of the product containing more than 1mg of a controlled drug such as THC. Neither rule means a product is free of THC.

Full spectrum, broad spectrum and isolate for drivers

Whichever type you choose, ask for the lab report for your batch, not just a general certificate. We’ll be honest: no CBD product can guarantee a negative drug test, ours included, because a lab test can only show that THC was below the level it can detect. More detail in full spectrum vs broad spectrum vs isolate and what is CBD isolate?

All Evopure CBD products are broad spectrum with 0% THC, made in the UK and tested by independent ISO 17025 labs. Batch reports are on our lab testing page. If you would rather not take CBD by mouth, our balm is applied to the skin instead.

Can CBD affect your driving?

CBD does not get you high. Our guide does CBD get you high? explains why. Studies of driving so far are reassuring but small:

• In a 2020 trial with 26 healthy adults on real roads in the Netherlands, vaporised cannabis that was mostly CBD did not increase lane weaving compared with a placebo, while cannabis high in THC did.
• A separate trial, by the Australian team behind the roadside test study above, found that oral CBD at 15mg to 1,500mg did not cause feelings of intoxication and was unlikely to impair simulated driving, although some of its driving results were inconclusive.

These studies were short and in healthy volunteers, so they can’t tell you how you will react. Some people do feel drowsy after CBD, especially at higher amounts, when they first start, or with evening blends that contain other ingredients. If that happens, don’t drive: driving while unfit is an offence under section 4 whatever the cause.

If you have had a drink as well, the safest choice is not to drive. See CBD and alcohol.

How long after taking CBD can you drive?

There is no official waiting time for CBD, because it has no drug-driving limit. What matters is how you feel. Timing varies by format, and our guide to how long CBD takes to work has typical timings for oils, capsules and gummies.

Try any new product, strength or amount at home on a day you are not driving. Also bear in mind that CBD can stay in your blood for a long time: in one trial it was still measurable more than four weeks after a 1,500mg dose. Roadside tests look for THC rather than CBD, but it is one more reason to choose a product with no detectable THC. See how long CBD stays in your system.

CBD, medicines and driving

GOV.UK says it is illegal in England, Scotland and Wales to drive with legal drugs in your body if they impair your driving. Some prescription medicines also have their own limits, including diazepam, lorazepam, temazepam, methadone and morphine. If you take these as prescribed and they don’t make you unfit to drive, you can still drive, even above the limit.

The NHS says CBD and THC can affect how other medicines work, and the FSA advises that people taking any medication should not take CBD unless under medical direction. If you take a prescription medicine, speak to your GP or pharmacist before using CBD, and ask whether the combination could affect your driving. Our guide can CBD interact with medication? explains which drugs to check.

Prescribed medical cannabis and driving

Prescribed cannabis-based medicines are different from CBD food supplements. The NHS notes that most cannabis-based products contain some THC, so a patient taking them exactly as directed could be above the 2 microgram limit while feeling perfectly well.

Section 5A includes a statutory medical defence. It covers you if the drug was prescribed or supplied to you for medical purposes, and you took it in line with your prescriber’s directions and the manufacturer’s instructions. It doesn’t apply if you ignored advice about how long to wait between taking the medicine and driving.

Department for Transport guidance adds that it may help to carry evidence of your prescription when driving, and that the defence does not cover the section 4 offence, so you can still be prosecuted if your driving is impaired. Because it is built around medicines prescribed or supplied for medical purposes, it isn’t something to rely on for a CBD product bought in a shop or online.

For how prescriptions work, see medical cannabis in the UK. If you have a prescription, ask your specialist for advice on driving.

Driving for work

If you drive for work, your employer’s rules may be stricter than the law. HSE guidance says employers should never allow anyone who is unfit through drink or drugs to drive, should set out their drug and alcohol policy in the employment contract, should let workers declare prescription and off-the-shelf medication, and should consider random testing.

Workplace tests can be different from police roadside kits. Before you use any CBD product:

• read your employer’s drug and alcohol policy, or ask HR or occupational health;
• tell them if the policy asks you to declare supplements;
• keep the batch lab report for the product you use.

If you are in a safety-critical role, check with your employer first, and you may decide not to use CBD at all. Our drug test guide covers what to do if a test comes back positive.

If you are stopped by the police

A roadside kit is a screening test. If it is positive, or police think you are unfit to drive, you will be arrested and asked for a blood or urine sample at a police station. That sample is analysed to see whether you were over the limit.

According to GOV.UK, a drug-driving conviction can mean:

• a minimum one-year driving ban;
• an unlimited fine;
• up to six months in prison;
• a criminal record, with the conviction shown on your licence for 11 years;
• a significant rise in your car insurance costs.

In Northern Ireland the fine can be up to £5,000. Causing death by careless driving under the influence of drugs can carry a life sentence. If you are charged, get advice from a solicitor.

How to use CBD safely if you drive

1. Choose broad spectrum or isolate, never full spectrum.
2. Check the batch lab report shows THC not detected, and keep a copy.
3. Avoid untested products, including cheap imports, gummies and vapes with no batch report. See can you vape CBD oil?
4. Try new products at home first, and see how they affect you before you drive.
5. Start low. Our CBD dosage guide shows how many drops make 10mg.
6. Keep evening blends for the evening, such as our Sleep CBD Oil, rather than before a drive.
7. Check your medicines with your GP or pharmacist, especially any that already warn about driving.
8. Don’t drive if you feel drowsy, dizzy or not yourself, whatever you have taken.

Related guides

• The same THC rules apply to drinks: see CBD drinks, driving and drug tests.
• If you drive for work, a broad spectrum product with a THC result on its lab report is the safer choice: see our CBD capsules guide.
• If CBD makes you drowsy, take it in the evening rather than before a drive. Our guide to when to take CBD oil explains how.