Availability, retail price and potency of legal and illegal cannabis in Canada after recreational cannabis legalisation.

In the 2 months post-legalisation, illegal cannabis was less expensive, with higher labelled THC content than legal cannabis, although the scope of these differences was more modest than estimates from other crowdsourced and self-reported data. Direct monitoring of cannabis price and potency from legal and illegal retailers is needed to examine the impact of legalisation over time.