IBJ 2025 Marriage White Paper: Marriages with an Age Gap of 10 Years or More Account for Only 4.6%, with ¥15 Million Income Marking a Key Threshold

IBJ, a Japanese marriage agency operator, released the sixth installment of its 2025 IBJ Marriage White Paper, focusing on the correlation between age-gap marriages and economic power. Based on an analysis of data from around 20,000 people who got married through its network, the company found that marriages with an age gap of 10 years or more account for only 4.6% of all cases. More than half of married couples were concentrated within the range of same age to a four-year age gap. The most common pattern was men being one to two years older, at 22.9%, followed by men being three to four years older, at 21.4%. Same-age marriages accounted for 11.1%. IBJ suggests that an age gap of one to four years tends to make it easier for couples to share similar cultural backgrounds and common topics, reflecting the growing importance of shared values and equal relationships in modern marriage. The analysis also found a certain proportional relationship between men's annual income and the age gap with their marriage partners. Men earning in the ¥3 million range had an average age gap of about one year, while even those earning in the ¥10 million range averaged only about four years. However, once annual income exceeded ¥15 million, the age gap expanded more noticeably: about seven years for those earning ¥15 million to ¥20 million, and about eight years for those earning over ¥20 million. Among men who married women at least 10 years younger, the average annual income was ¥11.7 million, indicating that large age-gap marriages tend to be associated with higher economic power. By contrast, in cases where the woman was five to nine years older, the man's average annual income was ¥5.35 million, about ¥1 million lower than in same-age marriages. The survey is based on activity data from 19,112 members who married through the IBJ marriage agency network. This article focuses on 9,394 couples who married within IBJ, excluding external marriages. The target period is January 1 to December 31, 2025. IBJ plans to publish the 2025 Marriage White Paper every Thursday over 15 weeks, with future releases covering shifts such as declining age-gap marriages among seniors, shrinking age gaps between spouses, and the increase in marriages where the wife is older.