On 9 September the first follow-up measurement of the Wietexperiment was published. This is the trial in which the Netherlands is testing a closed, legal cannabis supply chain for its coffeeshops. After a year of fully regulated supply in ten municipalities, the picture is clear on flower choice and price, and much less comfortable on hash.
What was measured and who did it
The report was prepared by Breuer&Intraval, RAND Europe and the Trimbos Institute, commissioned by the WODC, the research centre of the Ministry of Justice and Security. It covers the period from 7 April 2025, when coffeeshops in the ten participating municipalities switched to selling only product from licensed growers, to the first quarter of 2026. It compares them with ten other municipalities that keep the traditional tolerance policy.
The data set is substantial: 85 interviews, 865 surveys of coffeeshop customers, 441 of residents and workers in the areas concerned, and an analysis of 134 product menus. According to Cannabisindustrie.nl, the average price of flower in the trial municipalities fell from €12.06 to €10.08 per gram, while in the comparison municipalities it rose to €12.47.
A menu three times larger
The most visible change is at the counter. The average number of flower varieties on the menu rose from 10.8 to 34.2 in the trial municipalities, against an increase from 12.6 to 16.2 in the comparison group. Edibles, previously found in 34% of the shops visited, are now in 94%. Concentrates went from 17% to 70%, and vapes appear in 60% of shops.
Consumers also get more information, though there is room to improve: 56.7% of the trial coffeeshops state the THC percentage of their flower, averaging 23.6%. For hash the average reaches 37.2%, with products of up to 73%. The researchers single out the potency of edibles and vapes as an area that calls for better customer information.
The hash problem
The other side of the coin is hash. Its average price in the trial municipalities almost doubled, from €11.68 to €21.12 per gram. As reported by Business of Cannabis, illegal hash purchases grew in those areas. This is the report’s main warning: an expensive or scarce legal product pushes customers out of the regulated channel, even when the rest of the range works.
Otherwise there are few surprises. Visitor numbers and self-reported use are stable, neighbourhood liveability barely changes (with a slight rise in complaints about noise and loitering), and the growers themselves have moved from worrying about meeting demand to talking about overproduction.
What cannabis businesses can take from it
- Scale matters more than the licence. Ten authorised growers are enough to supply ten municipalities and still produce surpluses. Anyone planning capacity for a regulated market should model real demand, not a theoretical ceiling.
- Hash is a technical and cost challenge. Producing it legally at a competitive price remains unsolved. There is room for extraction and processing suppliers.
- Range and price keep customers. Where the legal offer is broad and cheap, buyers stay in the regulated channel. Where it is not, they go back to the illicit one.
- Labelling and potency will be in focus. THC data and information on edibles and vapes will be among the first things regulators review.
Timeline: 2026 to 2029
Three more annual measurements remain. The final report is due in summer 2028, and the Dutch government will decide in 2029 whether the model continues, expands or is dropped. For the rest of Europe, where other countries are testing or debating their own models, these figures are some of the little evidence available on how a complete legal chain behaves, from cultivation to sale.
How to size production, what happens with derived products and who supplies newly regulated markets will be central topics at Spannabis B2B Bilbao 2027, on 11 March in the VIP Hall of the BEC. If you work in cultivation, extraction or distribution and want to meet the people already operating in these markets, get your ticket or book a B2B table for your meetings.