Legal THC limit in France: 0.3%, measured on what?

The text of reference is the order of 30 December 2021 in its current version. Article 1 authorises "the cultivation, import, export and industrial and commercial use only of varieties of Cannabis sativa L. whose delta-9-tetrahydrocannabinol content is not higher than 0.30%". The variety must also be listed in the EU common catalogue or in the French one. The order applies the same maximum THC level, 0.30%, to hemp extracts and to the products that contain them.

Both conditions must be met. On the genetic side, the variety has to be listed and grown from certified seed by an active farmer. On the result side, the product has to stay under 0.30% Δ⁹-THC. A flower within the limit that comes from an unlisted variety fails the text. How a variety gets listed is explained in our article on the varieties in the EU catalogue.

Δ⁹-THC is the form of THC responsible for the psychoactive effect. CBD has none, and the other differences are covered in THC and CBD: the differences.

Nobody derived the 0.3% figure from an effect on humans. The Canadian botanists Ernest Small and Arthur Cronquist proposed it in 1976 to classify Cannabis sativa plants: the "drug" type above, hemp below. The Canadian Food Inspection Agency notes that this dividing line remains the reference in North America.

For a long time the European Union used a lower figure for its farm aid. Article 32 of Regulation (EU) No 1307/2013 accepted hemp areas only if their varieties had a THC content "not exceeding 0.2%". Regulation (EU) 2021/2115, which has governed the common agricultural policy since 1 January 2023, raised that ceiling to 0.3% in its article 4. The French order of December 2021 applied 0.30% from the day it was published.

A page that still quotes 0.2% describes the rule as it stood before 2022.

On 19 November 2020 the Court of Justice of the European Union delivered the Kanavape ruling (C-663/18). A member state, it held, cannot ban the sale of CBD lawfully produced in another member state, unless a proportionate public health ground justifies it. At paragraph 76, the Court found that bringing CBD within the definition of narcotic drugs under the 1961 Convention would run counter to the spirit of that text, since CBD has no known psychoactive effect. The reach of the ruling is set out in our article on the Kanavape ruling.

The order of 30 December 2021 applied the consequences of that ruling, yet banned the sale of raw flowers and leaves to consumers. The Conseil d'État's interim relief judge suspended that ban on 24 January 2022. On 29 December 2022 the Conseil d'État annulled it, finding no evidence that flowers under 0.30% Δ⁹-THC carry a risk that would justify a general and absolute ban. The rest of article 1, threshold included, remained in force. Our article on the order that tried to ban flowers tells the story.

The annex to the order sets out the method for checking crops. The sample is dried to constant weight and analysed by gas chromatography with a flame ionisation detector. The result is given in grams of Δ⁹-THC per 100 grams of sample, to two decimal places, and it "carries a tolerance of 0.03% in absolute value". If a result comes out high, the stricter procedure samples the top third of 200 plants.

What the living plant mostly contains is THCA, the acid form of THC, which has no psychoactive effect until heated. Gas chromatography heats the sample. A 2022 study in Frontiers in Chemistry reproduced the conditions of the official method, with the injector at 300 °C, and nearly all the THCA turned into THC. The result is therefore close to "total THC".

Most CBD certificates of analysis come from liquid chromatography (HPLC), which separates the two forms without heating the sample. They give one Δ⁹-THC line and one THCA line. The standard formula for estimating total THC is Δ⁹-THC + 0.877 × THCA, where the 0.877 factor corrects for the mass lost when THCA gives up its carboxyl group.

Whatever the product, read both lines. Each one is explained in our guide to reading a certificate of analysis, and the page on THCA covers its chemistry. The laboratory page describes the measurement methods.

The 0.30% threshold applies to a product and grants no tolerance to the person using it. Article L235-1 of the Highway Code punishes driving after a blood or saliva test shows use of a controlled drug with three years in prison and a €9,000 fine. On 21 June 2023 the Court of Cassation ruled that the permission to sell products under 0.30% THC has no bearing on this offence, which is established whatever the dose taken.

A compliant hemp product may contain traces of THC, and a saliva test looks for the molecule itself, whatever the percentage in the original product. The known detection windows are in our guide to CBD and saliva testing.

Staying under 0.30% Δ⁹-THC does not make a product legal if it contains a controlled molecule. The ANSM added HHC, HHCO and HHCP to the list of controlled drugs from 13 June 2023, then H4CBD, THCP and other derivatives from 3 June 2024. These molecules are described on our pages on HHC and H4CBD.

Food law is a separate matter. A CBD product meant to be swallowed falls under the EU regulation on novel foods, and foods containing CBD are not authorised in France; the full picture is in our article on CBD regulation in 2026. The threshold also says nothing about where a compliant flower may be smoked. The places where smoking is banned are listed in our article on smoking CBD in public.