Daily Life Handbook
Basics tips on formal wear
Proper formal attire for a party or an event may differ depending on one's position and the time in which the occasion takes place. It is typical to dress formally in case of family or the guest of honor, semiformal for relatives, and informally for an acquaintance or friends.
When dressed western style, formal attire for men will be a cutaway coat during the day and swallow-tailed coat and tuxedo for the evening. For women, an afternoon dress for daytime and evening dress for the evening.
When dressing Japanese style, formal attire will be crested haori (a half-coat) and hakama (a divided skirt) for men, and a black tomesode kimono for married women and a color tomesode kimono for unmarried women.
Semiformal attire will be director's suit or a black suit during daytime and a tuxedo in the evening for men. Women's semiformal attire will be an afternoon dress during daytime and cocktail dress for the evening. If unmarried, women may wear a furisode (long-sleeved) kimono as well.
For informal attire, men will wear a dark suit, such as navy or gray, and mainly a dress or two-piece suit for women. Japanese style semiformal attire will be a houmongi (ceremonial kimono) or iromuji-montsuki (crested solid color) kimono whether married or not, and iromuji (solid color) kimono or tsukesage kimono will be suitable for informal occasions.
Black will be the base color for mourning. Men will wear a black full-dress suit, but wearing a black tie with navy or gray suit is also acceptable when going to the occasion directly from the office. Women will wear a solid black short sleeve dress with a black long sleeve jacket. Any shiny or glossy fabric should be avoided and skin exposure shall be limited.
For Japanese style, it is common to wear a komon kimono with a black obi (band) or black crested haori (half-coat).
What has been introduced here is a typical example for formal attire. Consult with ceremonial halls, bridal production companies and funeral houses for further details or for any specific advice.
Source: Kankonsousai Gojo Kyoukai