Around the world, women marry earlier than men, but it is not well understood why this gender gap exists. Using panel data collected in Nepal, the authors investigate whether attitudes about marital timing held by unmarried youth and their parents account for women marrying earlier than men. They also examine whether the influence of timing attitudes differs by gender. On average, unmarried youth and their parents viewed 20 to 25 as acceptable ages for women to marry, whereas ages 23 to 30 were appropriate for men. In turn, women entering the acceptable marriage age range earlier than men accounted for a third of the gender gap in marital timing. The influence of youth and parents' timing attitudes did differ by gender, but only at the extreme. When they were much too young for marriage, both genders were less likely to marry, but this dampening effect was substantially larger for women.