| Coming of Age Day | |
|---|---|
 Young women celebrating Coming of Age Day at Meiji Shrine in Tokyo, 2008 | |
| Official name | 成人の日 (Seijin no Hi) |
| Observed by | Japan |
| Type | Public |
| Significance | Congratulates and encourages all those who have reached the age of maturity (18 years old) over the past year and celebrates adulthood |
| Date | Second Monday in January |
| 2023 date | January 9 |
| 2024 date | January 8 |
| 2025 date | January 13 |
| 2026 date | January 12 |
| Frequency | annual |
Coming of Age Day (成人の日, Seijin no Hi) is a public holiday in Japan held annually on the second Monday of January under the Happy Monday System. It is held in order to congratulate and encourage all those who have already reached the age of maturity between April 2 of the previous year and April 1 of the current year, and to help them realise that they have become adults. Festivities include coming of age ceremonies (成人式, seijin-shiki) held at local and prefectural offices, as well as after-parties among family and friends.