We investigate whether and how time pressure affects performance. We conducted a field experiment in which students from an Italian University are proposed to choose between two exam schemes: a standard scheme without time pressure and an alternative scheme consisting of two written intermediate tests, one of which to be taken under time pressure. Students deciding to sustain the alternative exam are randomly assigned to a “time pressure” and a “no time pressure” group. Students performing under time pressure at the first test perform in absence of time pressure at the second test and vice versa. We find that being exposed to time pressure exerts a negative and statistically significant impact on students’ performance. The effect is driven by a strong negative impact on females’ performance, while there is no statistically significant effect on males. Both the quantity and quality of females’ work is hampered by time pressure. Using data on students’ expectations, we also find that the effect produced by time pressure on performance was correctly perceived by students. Female students expect a lower grade when working under time pressure, while males do not. These findings contribute to explain why women tend to shy away from jobs and careers involving time pressure.