An analysis of 2018–19 Drug Use Monitoring in Australia data suggests 64 percent of police detainees obtained methamphetamine from someone they knew, while 28 percent bought from a dealer. The most common location to obtain methamphetamine was the home of a known person. Detainees reporting methamphetamine dependence were more likely to buy from a dealer and those injecting methamphetamine were more likely to obtain it at an agreed public location. The findings suggest detainees most commonly obtained methamphetamine through closed drug markets using social supply. However, detainees with more harmful patterns of use also commonly used semi-open markets.