The COVID-19 pandemic and its concomitant restriction measures drastically altered the routines and learning formats of students from all levels. In addition, it has been shown that pandemic-related stress negatively impacted their mental health and cognitive functioning. Undergraduates have been signaled out as one of the populations most vulnerable to pandemic-related stressors. The following work examined the link between executive functions, perceived stress and reading comprehension among Argentinean university students during lockdown measures. In addition, potential effects of reading habits and screen exposure were considered. An executive function behavioral rating scale (ADEXI), a reading comprehension test and the PSS-10 stress questionnaire were administered to two-hundred social science students through an online survey. Executive difficulties increased with perceived stress, while lower inhibition was associated with longer TV times and being male. Stress and executive function associations can be interpreted as a detrimental effect, reverse or bidirectional causation. In turn, working memory issues led to worse comprehension (mediating the impact of perceived stress) while distal factors such as print exposure and mother education were positive predictors of reading outcomes (as expected). This finding suggests that undergraduates' difficulties to manipulate online information interfered with expository text processing, resulting in poorer comprehension performance.