The Rise of Assortative Marriage in Japan: A Reflection of Economic and Social Shifts

n post-pandemic Japan, the trend of “assortative marriage” — where individuals select partners with similar traits such as age, education, and income — has become a notable social phenomenon. Despite the declining number of marriages, assortative marriage is gaining prominence, signaling a shift in societal norms and preferences. This trend is especially evident in marriages where partners are of similar age, education level, or economic standing, highlighting deeper changes within Japanese society.

Age and Marriage: The Rise of Same-Age Unions

One of the most striking aspects of this phenomenon is the increase in same-age marriages. In 1970, only 10.3% of first-time marriages in Japan were between partners of the same age, but by 2022, this figure had climbed to 24.3%. In contrast, traditional marriages where the husband is older than the wife, known as “husband-elder marriages,” have significantly declined, dropping from 80% in 1970 to 53.4% in 2022.

Although the proportion of same-age marriages has increased, the total number of marriages in Japan continues to decline. From 1970 to 2022, the number of same-age marriages decreased by approximately 22,000, indicating that while the trend is growing, it is not enough to…