In an extraordinarily course of events new research has found out that unless married couples are allowed to adopt separate surnames, all Japanese citizens will share the same family name in 500 years, prompting a call to modernize a civil code established in the late 1800s. In contrast to many other major economies that have abandoned this practice, Japan maintains a legal requirement for married couples to share the same surname. Typically, wives adopt their husband’s surname, and same-sex marriages remain unrecognized in Japan.
Conducted by Hiroshi Yoshida, an economics professor at Tohoku University, the study forecasts that if Japan persists in requiring couples to share a single surname, every Japanese individual will be identified as “Sato-san” by the year 2531.
As reported by Myoji Yurai, an organization that monitors Japan’s extensive database of over 300,000 surnames, Sato presently holds the top position as the most common surname, followed by Suzuki. Takahashi ranks third in popularity. Myoji Yurai’s website indicates that approximately 1.8 million individuals out of Japan’s total population of 125 million bear the surname Sato.
Yoshida acknowledged that his projections relied on various assumptions. However, he emphasized that the objective was to utilize statistical analysis to illustrate the potential impacts of the current system on Japanese society, aiming to raise awareness about the issue.
“If everyone becomes Sato, we may have to be addressed by our first names or by numbers,” he said, according to the Mainichi. “I don’t think that would be a good world to live in.”
Based on Yoshida’s calculations, the percentage of individuals with the surname Sato rose by 1.0083 times from 2022 to 2023. If this rate remains consistent and no amendments are made to the surname legislation, approximately half of the Japanese populace will bear that name by 2446, with the figure reaching 100% by 2531.
The study presented an alternative scenario drawn from a 2022 survey conducted by the Japanese Trade Union Confederation. According to the survey, 39.3% of 1,000 employees aged 20 to 59 expressed a preference to share a surname even if given the option to use separate ones.
In light of this alternative scenario, Yoshida, whose study was commissioned by the Think Name Project and other organizations advocating for the legalization of surname choice, projected that by 2531, only 7.96% of the Japanese population would bear the surname Sato, as reported by the Mainichi Shimbun.
The scenario would be altered if Japan’s government yielded to increasing pressure to permit married couples to adopt distinct surnames. Advocacy groups pushing for a revision in the legislation regarding married surnames are optimistic that their campaign will gain momentum with the realization that surnames such as Suzukis, Watanabes, and even those like Yoshida—ranking as the 11th most common surname—might eventually vanish.
Conservative members of the ruling Liberal Democratic Party (LDP) argue that altering the law would “undermine” family cohesion and potentially lead to confusion among children.
