Background <p>Transactional sex has gained public health attention in recent times because of its contributions to sexually transmitted infections and unwanted pregnancy among young women in sub-Saharan Africa. However, empirical data on the extent of this practice are lacking in Ghana. This study provides baseline information on the prevalence of transactional sex practice and associated factors among young women in a tertiary institution in Northern Ghana.</p> Methods <p>A quantitative cross-sectional survey was conducted among 340 sexually active young female students. Stratified and simple random sampling techniques were used to sample respondents. Data were collected online using a pretested questionnaire. The prevalence of transactional sex and other socio-demographic characteristics were analysed descriptively using frequencies and percentages. A logistic regression model was used to determine predictors of transactional sex and assess the links between transaction sex and other risky sexual behaviours.</p> Findings <p>Respondents were aged 18–31 years, and mean age was 24.94 (SD = ± 4.87). The prevalence of ever engaging in transactional sex was 23.8%, and 16.8% reported engaging in transactional sex in the past 12 months prior to the study. Nearly 65% of those who reported engaging in transactional sex in the last 12 months have done so at least four times. The odds of engaging in transactional sex were lower among older respondents (AOR: 0.140, 95%, CI: 0.032–0.605, <i>p</i> = 0.008); but higher for early sexual debut (AOR: 2.745, 95%, CI: 1.068–7.060, <i>p</i> = 0.036), area of residence (i.e. being peri-urban) (AOR: 8.300, 95%, CI: 1.655–41.617, <i>p</i> = 0.010), insufficient family support (AOR: 5.903, 95%, CI: 1.515–23.006, <i>p</i> = 0.011), and frequently using at least two social media applications (AOR: 3.893, 95%, CI: 1.276–11.877, <i>p</i> = 0.017). Respondents who engaged in transactional sex reported higher odds of contracting STIs (AOR: 3.580, CI:1.059–12.099, p 0.040), and having an abortion (AOR: 2.616, CI: 1.037–6.598, p 0.042) in the last 12 months.</p> Conclusion <p>Targeted comprehensive sexual and reproductive health and rights education interventions are needed on the campuses of institutions of higher learning to enable young women negotiate safe sex and sexual relationships. In addition, there is need to promote contraceptive use (especially those that offer dual protection) among young women on the campuses of tertiary institutions to minimise STIs infection and unwanted pregnancy. Economic empowerment programmes such cash transfers to identifiable impoverished female students, scholarships and grant opportunities and discounted fees would also be critical to preventing and/ or minimising the occurrence of transactional sex among young women.</p>