Initial findings from the Netherlands’ landmark ‘controlled cannabis supply chain experiment’ were submitted to the House of Representatives on September 9, the first published findings since the T0 baseline report, published in March 2024 (covering data collected in 2022).
The new data covers the period from April 7, 2025, through the first quarter of 2026, the first full year of fully regulated cannabis sales.
Multiple production delays extended the experiment’s already staggered rollout. All ten participating municipalities came online on June 17, 2024, but constraints around domestically grown supply meant they entered a transition phase (overgangsfase), allowing coffeeshops to sell a mix of regulated and legacy-sourced cannabis.
That phase ended on April 7, 2025, when all cannabis flower sold in participating stores was required to come from regulated growers.
What does the data say?
The research consortium behind the study, Breuer&Intraval, RAND Europe and the Trimbos-instituut, coordinated by the Ministry of Justice and Security’s WODC research unit, compared the ten intervention municipalities, where coffeeshops may sell only regulated products, against both comparison municipalities that kept the old illicit toleration policy and the pre-experiment baseline.
Visitor numbers, frequency and self-reported use were unchanged at every coffeeshop in the sample.
Perceived neighbourhood liveability held steady, though reports of loitering, traffic and noise edged up in both groups versus baseline, running slightly higher in intervention areas. About one in five respondents in both groups said they had been a crime victim in the neighbourhood in the past six months, in line with national rates.
Its impact on the illicit market was also tracked. Consumers cited lower prices, better perceived value and the ability to buy in bulk as reasons to keep buying outside of regulated supply.
Illegal hash purchases specifically rose in intervention municipalities during the period, against a fall in comparison municipalities, which researchers suggested may reflect a shortage of legal hash early in the rollout.
One issue raised by municipalities, coffeeshop owners, growers and inspectors was in relation to high-THC editibles, vapes and concentrates, amid concerns consumers were not always informed of their strength or appropriate dosage.
In response, the cabinet said it had revised the product leaflet, commissioned the Trimbos Institute to study high-potency products specifically, and committed to bi-annual consultations with participating municipalities.
Following the T0 baseline, this batch represents T1, with T2 and T3 follow-ups still to come before a full evaluation in 2028, and a cabinet decision on the programme’s future expected in 2029.
From supply shortages to oversupply concerns
Researchers interviewed five of the ten licensed growers and two transport companies directly, noting that all of the ten licence holders were operational over the T1 reporting period.
Notably, early concerns about supply shortages have now been turned on their head, with growers raising concerns about oversupply.
“Because all growers are currently operational and can produce increasingly large quantities, they are now approaching a situation of overproduction,” the report states, paraphrasing the interviews.
“This causes price pressure and growing stockpiles among growers. At the same time, demand and supply for certain product types, such as hash, continue to lag.” Growers are now reportedly diverting some capacity toward hash production in response.
According to the report’s pricing data, domestically grown regulated cannabis flower fell from €11.55 to €10.09 a gram in intervention municipalities between baseline and T1, while comparison municipalities barely moved (€11.23 to €11.04).
Hash moved the opposite way and far more sharply. It nearly doubled in price from €11.67 to €21.12 a gram in intervention municipalities, while seeing a modest rise in comparison municipalities (€10.62 to €12.65).
Local reporting from Breda and Tilburg, the two municipalities that ran the original pilot phase from December 2023, has suggested that sellers are struggling to find a workable track-and-trace system.
