Couples-based HIV testing and counseling (CHTC) is currently available only for gay male couples in the United States, but other types of couples could benefit from this service. Our cross-sectional, online study collected data from 536 partnered adults to assess interest in using CHTC and associated factors. Adjusted odds ratios were calculated with ordinal logistic regression to analyze factors associated with greater interest in using CHTC. Most participants were female, White, non-Hispanic, and/or students who were dating exclusively and sexually active. Participant interest in using CHTC varied. Greater interest was associated with identifying as bisexual or questioning (adjusted odds ratio [aOR] 2.53, p < .05); having a sexual agreement (aOR 6.82, p < .001); and inconsistent or no condom use for anal sex (aOR 0.31, p < .05). These findings lend support for additional research about how best to extend and offer CHTC to a wider variety of couples.