BACKGROUND: In recent cohorts, obtaining an advanced educational qualification has become the norm across European countries and women now outnumber men in tertiary education, possibly leading to shifts in men’s preference for equally or higher-educated partners. Women with at most a basic educational qualification might therefore be increasingly marginalized in the partnering market. OBJECTIVE: We investigate whether women with lower educational qualifications are less likely to ever enter a cohabiting union in different regions of Europe. We analyse whether this association has changed across cohorts and compare it to the results for men. METHODS: We apply logistic regressions to recent European Social Survey data from 2002–2022 from 28 countries, grouped into four regions. We include women and men born between 1960 and 1985. RESULTS: In recent cohorts in Western and Southern Europe, compared to higher-educated women the probability of 35 to 45-year-old, lower-educated women having ever entered a cohabiting union has declined significantly. In older cohorts, we find the opposite. Our findings point in a similar direction for the Nordic and Eastern European regions, but the associations remain statistically insignificant. We find that union formation patterns between lower-educated men and women converge in the Western and Southern European regions. CONCLUSIONS: Our results suggest that women with lower educational qualifications are becoming increasingly marginalized in the partnering market. CONTRIBUTION: We add to the limited cross-country research on the educational gradient of women entering a cohabiting union and on convergence between men and women in union formation patterns.