The release of live baitfish by anglers has been identified as a high-risk pathway for the introduction of aquatic invasive species due to the potential for invasive fish, invertebrates, or pathogens to be released simultaneously with the baitfish. Consequently, the release of live baitfish is illegal in many jurisdictions, but little is known about compliance rates or angler motivations for illegal release. To assess the incidence of live baitfish release in Minnesota, USA, a state with significant live baitfish use and substantial recreational fisheries, we administered a mail survey to a random sample of 4,000 anglers who held a 2018-2019 annual fishing license and received 671 completed responses. To mitigate potential recall bias, we also administered 345 intercept surveys at waterbody access sites around the state to ask anglers about their current day’s behaviors. A total of 481 (72%) of the mail survey respondents reported that they used live baitfish and of those, 99 (20%) reported that they release their leftover live baitfish into the water at least some of the time. Of the anglers surveyed at waterbody access sites, 59 (19%) were using live baitfish on the day they were surveyed and of those, 11 (18%) released their leftover baitfish into the water. The reasons anglers provided for releasing their baitfish included convenience and their mistaken understanding that released baitfish benefit the recipient ecosystem. The potential for invasive species introductions through baitfish releases is high given the reported rate of baitfish releases. However, there is also significant opportunity for management interventions aimed at changing perceptions and providing convenient disposal alternatives to illegal release to reduce the risk presented by this pathway.