Introduction and aim. Substance abuse and its associated problems are a global concern. Young adults, particularly college- going students, remain among the highest at-risk groups for various substance use disorders. So, this study was conducted to find out the prevalence of substance use and its correlates among undergraduate (UG) university students. Material and methods. We did an online cross-sectional survey among 1003 undergraduate university students across India using a pre-structured, self-reported questionnaire consisting of basic demographic details, standard tool (WHO-ASSIST), and the results were tabulated. A multivariable binary logistic regression analysis was performed to find out the correlates of substance use and Pearson correlation to find a correlation between ASSIST scores. Significance was attributed to a p-value <0.05. Results. A total of 320 (31.9%), 167 (16.7%), and 125 (12.5%) among 1003 students used alcohol, tobacco, and cannabis respectively. 70 (21.9%), 116 (69.5%), and 62 (49.6%) were at moderate-high risk of abuse for alcohol, tobacco, and cannabis respectively. There was a strong positive statistically significant (p<0.001) correlation between all three substance-specific scores (Pearson’s Coefficients r = 0.643, 0.763, and 0.725 respectively). Conclusion. One, two, and three out of every ten students used cannabis, tobacco, and alcohol respectively. Many of them fall into the moderate-high risk category. The data suggest that a student at high risk for any one substance is also at a higher risk of using another substance as well. This calls for an integrated ‘bundle’ approach to focus on all substances together as one unit.