The primary objective of this study was to determine Filipino undergraduate students’ perceptions of acts of academic dishonesty within the context of online learning. Additionally, the study aimed to assess whether there are significant differences in their responses when grouped by demographic factors. Following Waltzer and Dahl’s Situated Decision-Making Framework, this study assumed that perceptions of academic dishonesty are positively related to student engagement. Students who do not view an act as cheating are more likely to engage in it. A total of 1547 undergraduate students from a private higher education institution in Laguna, Philippines, were surveyed. The sample size was determined using the Raosoft Sample Calculator. Descriptive statistics, the Mann–Whitney U Test, and the Kruskal–Wallis Test were employed to analyze the collected data. Results indicated certainty among respondents regarding acts of academic dishonesty in online learning. Significant differences were found in students’ perceptions of cheating and plagiarism based on sex and school demographics. Serious attention should be given to providing consistent information across different schools and departments. Effective mechanisms to raise awareness of academic dishonesty and enhance the level of academic integrity should be implemented uniformly in all schools, departments, and colleges within the university.