Synthetic opioid overdose mortality among young adults has risen more than 300% in the USA since 2013, primarily due to the contamination of heroin and other drugs with illicitly manufactured fentanyl. Rapid test strips, which can be used to detect the presence of fentanyl in drug samples (before use) or urine (after use), may help inform people about their exposure risk. The purpose of this study was to determine whether young adults who use drugs were willing to use rapid test strips as a harm reduction intervention to prevent overdose. We hypothesized that those who had ever overdosed would be more willing to use the test strips.