Seijin no Hi: Why Japan Still Celebrates Adulthood at Twenty

On the second Monday of January, the plazas outside city halls and concert halls across Japan fill with colour. Young women in furisode, formal kimono with long, swinging sleeves, arrange fur stoles and pose for photographs. Young men in dark suits or traditional hakama (pleated trousers) shake hands, tease each other and wait to be called in. It is Seijin no Hi, Coming of Age Day, and it is among the most photogenic mornings of the Japanese year.

The day is a national holiday celebrating people who are becoming adults. This guide covers its roots in ancient court rituals, the youth festival that inspired the modern version, the 2022 change in the legal age of adulthood and why many towns still hold ceremonies for twenty-year-olds, what people wear, what happens inside the hall, and how visitors can enjoy the day respectfully.

What Seijin no Hi Is

Seijin no Hi (Coming of Age Day) is a public holiday on the second Monday of January. It is dedicated to celebrating and encouraging young people as they enter adulthood. Local governments organise ceremonies called seijin-shiki, held in the morning or around midday, and anyone who has reached the age group being honoured is invited.

The date has not always been fixed to a Monday. The postwar holiday law set it as January 15 in 1948. A later reform, which took effect in 2000, moved it to the second Monday of January, creating a long weekend. As a result, the day now falls somewhere between January 8 and January 14.

Ancient Roots: Genpuku and Mogi

The idea of marking adulthood is old. In the Nara period (710 to 794), a ritual called genpuku was introduced from China to mark the passage of boys of the court into manhood, around the age of 12 to 16. The boy changed his clothes and hairstyle and was presented in adult dress. Girls of the upper class had a similar rite, called mogi, in which they put on adult dress and hairstyle.

Over the following centuries the custom spread beyond the court, to the warrior class and eventually to commoners in simpler forms. These rites often took place around the New Year, which is one reason the modern ceremony is held in January. Even though today's ceremony is a modern invention, it carries echoes of these older rituals.

Warabi 1946 and the Modern Ceremony

The modern ceremony traces its origin to a youth festival, called Seinen-sai, held in the city of Warabi in Saitama Prefecture in November 1946. It was designed to encourage young people in a time of rebuilding and to give them a sense of purpose and hope. The idea spread to other towns, and in 1948 the national government made Coming of Age Day a holiday.

Because the event is relatively young, some writers say it is more of a custom than an ancient tradition. Even so, it has become one of the best-loved moments in the Japanese calendar, and for many families it is a milestone worth dressing up for.

Eighteen or Twenty?

In April 2022, a revision of the Civil Code lowered the legal age of adulthood in Japan from 20 to 18, the first change in more than a century. At 18, people can sign contracts without parental consent and receive a ten-year passport, among other rights. Drinking, smoking and betting on public gambling remain restricted until 20.

The change did not end the ceremonies at twenty. Many municipalities still invite people who turn 20 within a set window, from April 2 of the previous year to April 1 of the current year, in part because eighteen-year-olds are often preparing for entrance exams in January. Some areas name the event a "gathering for twenty-year-olds," and the format varies by municipality, so check your local city hall's information if you want to know the rules in a particular town.

Furisode, Hakama and Suits

The furisode is the signature costume of the day. This is a formal kimono with long, swinging sleeves, usually brightly coloured and richly patterned, and it is traditionally worn by young women. Hair styling and make-up are a large part of the preparation, and many women add a fur stole around the shoulders.

Young men usually wear a dark Western-style suit, though some choose a kimono with hakama. Family kimono are often handed down, and many people rent theirs for the day. Some shrines offer packages that combine kimono rental, a photo shoot and a prayer, which is one way that families make the day special for a young person.

Inside the Ceremony

The ceremony is usually held in a theatre or a municipal hall and lasts less than an hour. A committee of new adults often helps organise it. Invitees receive a voucher in December, which they bring with them. The programme usually includes the national anthem, speeches by officials, thanks to educators and local groups, and greetings from local mascots.

Speakers encourage the new adults to take on responsibility and to take part in society. Some towns add a speech by a representative of the new adults, slideshows of childhood photographs, or small commemorative gifts. Afterwards, friends gather for photos, meals and parties. One city in Chiba holds its official ceremony at a theme park resort, and some towns now invite foreign students who turn 20 during their stay.

Snowy Regions and Other Calendars

In places where January weather makes travel in formal clothing difficult, such as parts of Akita, Yamagata and Niigata, some communities hold their ceremonies at a different time, such as the Golden Week holidays in May or the Obon season in August. This flexibility shows how seijin-shiki is a local event rather than a single national program.

Because each municipality chooses its own date, venue and format, the experience can differ greatly from town to town. Venues range from city halls and cultural centres to larger halls that attract young people, and the feel of the day can differ from one town to the next.

Other Ways Japan Marks Milestones

The success of Coming of Age Day has inspired newer milestone celebrations in some communities. Examples include totose no iwai, a celebration at age 10, nibun no ichi seijin shiki, the "half coming of age" ceremony held around age 10, and misoji shiki, a ceremony for people turning 30. These are local initiatives rather than national holidays, and they show how strongly Japanese communities value a moment to pause and mark growing up.

After the formal event, new adults often visit a shrine or temple to pray for their future, meet friends at a restaurant or izakaya (casual pub), or head to a theme park. The informal part of the day is as important to many people as the ceremony itself, and it is the reason town centres feel so festive on this Monday.

Seeing the Day as a Visitor

Visitors can enjoy the atmosphere on the morning of the second Monday of January near city halls, large concert halls and well-known shrines, where groups of new adults gather. It is a cheerful scene, and a polite smile is usually welcomed.

If you want to take photographs, ask first, particularly for close portraits, and keep away from the ceremony entrances. Avoid blocking pathways, and do not touch the furisode or the fur stoles. The ceremonies themselves are for invited residents, so enjoy the scene from outside. Check the local city's official website for the date, as arrangements differ, and wear warm clothes, since January mornings are cold.