<p>Incentives for participation can help enable more equitable public health research practices, particularly when working with people from structurally disadvantaged populations, such as people who use drugs or people experiencing homelessness. Administrative and perceived ethical advantages have solidified gift card incentives in research, even though participants tend to prefer cash incentives for their time, knowledge, and contribution of lived experiences. The use of cash instead of gift cards may merit fresh attention. Drawing from research with marginalized groups, we summarize concerns with gift cards and argue that cash incentives align better with public health ethical principles. Gift cards, while convenient for researchers, can constrain participants’ economic autonomy, foster mistrust, and magnify inequities and power imbalances between researchers and participants. Cash can help to affirm participants’ autonomy, reduce stigma, demonstrate solidarity and trustworthiness, and directly benefit health. Public health researchers and ethics boards can enable cash incentive practices that centre participant welfare over researcher and institutional convenience. In so doing, they uphold more equitable and respectful relationships with study participants, advancing both public health research and ethical standards.</p>