Key findings:

• From 1st May 2020 to 31st May 2021, 14 cryptomarkets were monitored weekly, of which 11 were active at the end of the reporting period.
• All of the three monitored cryptomarkets that closed during 1st May 2020-31st May 2021 had ceased operation before 31st January 2021, i.e. before the end of the reporting period for the last Bulletin.
• There was an average of 70,332 drug listings per weekly scrape in May 2021, representing a 126% increase in listings as compared to April 2021 (n=31,063), and a 7% decrease in listings as compared to May 2020 (n=75,617).
• This increase is largely attributable to the new monitoring of seven existing cryptomarkets during May 2021. Further investigation suggested these seven markets were operating from since February-July 2020 (but not captured in our monitoring), and thus caution is recommended for comparison between April and May 2021.
• In the last week of monitoring in May 2021, White House Market, Dark0de Market and ToRReZ Market were the three biggest cryptomarkets accounting for 74% of the observed drug listings.
• The greatest market share of drugs listed on the cryptomarkets from May 2021 to May 2020 was held by cannabis (29%), followed by MDMA (12%), cocaine (9%), benzodiazepines (8%), meth/amphetamine (illicit) (6%), and LSD (6%).
• The market share of cannabis showed the biggest percentage increase from 25% in May 2020 to 29% in May 2021. The biggest percentage decreases in market share were observed for MDMA (13% in May 2020 to 9% in May 2021), and for opioids (excluding heroin) (7% in May 2020 to 3% in May 2021).