The customary formal dance performed at many quinceañeras is a waltz.
The waltz is often presented as part of the honoree’s formal entrance or presentation, with the quinceañera dancing with members of her court and sometimes with a parent or other important relative. The choreography may be rehearsed for weeks or months.
Modern celebrations can include several styles of music and dance. A waltz may be followed by a surprise dance, popular songs, or regional dances, so it is not required at every quinceañera. The exact order and participants depend on local custom and family preference.
This question concerns the traditional formal dance, not every dance performed at the party. “Vals” is the Spanish word commonly used for a waltz and may appear in programs or invitations.