BACKGROUND: Drug checking is a harm reduction strategy that provides people who use drugs (PWUD) information about the composition of a substance. Drug checking has been identified as a key public health response to the continually evolving overdose crisis. METHODS: The New York City Health Department of Health and Mental Hygiene (DOHMH) partnered with existing syringe programs to launch a drug-checking pilot study. The study offered multiple point-of-care drug-checking technologies including fentanyl test strips (FTS) and Fourier-transformed infrared (FTIR) spectrometry, as well as secondary laboratory testing. Fentanyl positivity in major drug types was assessed for each drug-checking technology. RESULTS: Between November 2021 and December 2023, a total of N = 397 unique participants and drop-off samples contributed a total of N = 1644 samples for drug checking. The majority of samples were sold as opioids (n = 908), with fewer sold as cocaine (n = 314) and methamphetamine (n = 62). 95.3 % (852/894) of opioid samples produced positive FTS. FTIR and secondary laboratory testing resulted in a similarly high prevalence of fentanyl in opioid samples at 84.7 % (769/908) and 89.3 % (519/581), respectively. We did not observe the unexplained presence of fentanyl in samples sold as cocaine or methamphetamine. Further, we describe instances where discussions between technicians and PWUD provided important context that explained the presence of fentanyl in non-opioid samples. CONCLUSION: The majority of opioid samples submitted to DOHMH's drug-checking pilot study contained fentanyl. Comparatively, there was little evidence suggesting fentanyl in samples sold as cocaine and methamphetamine. The drug-checking pilot study's point-of-care service delivery model was effective in providing information to PWUD.