Age homo/heterogamy in romantic unions is given little attention in current gerontological research. Still partner age-differences are important for men’s and women’s relationship opportunities. This paper studies actual partner-age (age-difference) in cross-gendered unions, and ideal partner-age both for singles and respondents in unions. The study was carried out by a survey to 60–90 year old Swedes, currently either singles or in a cross-gender relationship (married, cohabiting, LAT) (n=1225). Unions follow a traditionally gendered age structure: 56% of men, but only 16% of women have a younger partner. This pattern is more pronounced: in first unions (p<.001) and unions initiated before 1970 (p<.01). For respondents in unions actual partner-age showed no significant correlation with union form or urbanity (modernity-hypothesis), and not with education or income (power-hypothesis). For respondents in unions Ideal Partner-Age correlates strongly (p<.001; R²=0,76) with actual partner-age (ideal slightly younger). Among single respondents, almost all (92%) single men and half of the single women (47%) prefer a younger partner (8,9 years younger on average for men; 2,2 for women). The proportion preferring a younger partner increases by age, leading to increasingly incompatible age ideals. Results will be discussed in relation to life-course theory; gender and power; the deinstitutionalization hypothesis.