Formal dress for women can vary depending on the occasion, but typically involves floor-length dresses, though midi or knee-length options can work for certain occasions. The formality of a dress tends to depend on length and tailoring, and its important to dress for the occasion and venue. The neckline of the dress can vary depending on personal preference, but ultra-plunging options may not be appropriate for certain occasions. Formal attire is located somewhere between cocktail and black tie, and dresses can be full or knee-length, in a wide spectrum of colors and styles. Here are some general guidelines for formal dress for women:

• Black Tie Event: This is the epitome of formal attire, and women are expected to wear their best floor-length gowns. Cocktail-length dresses or suits without jackets and ties are generally not allowed.

• Formal Event: This dress code is dressier than cocktail but less formal than black tie. Women can still wear floor-length gowns, but statement cocktail dresses are also acceptable. However, its generally advised to avoid anything too short.

• Semi-Formal Event: This dress code is less formal than formal attire and allows for more flexibility. Women can wear below-the-knee dresses, slip dresses, a dressy skirt and top, or an elegant pantsuit.

Its important to consider the venue and season when choosing a formal dress, as this can provide cues for how to approach your outfit. Additionally, its important to ensure that the dress is comfortable enough to last the whole night, especially if theres a chance that the evening may lead to the dancefloor.