Bual represents a group of Portuguese white grape varieties, which are widely grown in the Madeira Islands, Portugal, and are used to produce a medium-sweet style Madeira.

Bual represents a group of Portuguese white grape varieties, such as Boal Branco (or Boal Cachudo) and Malvasia Finca. Other forms of Bual/Boal include Boal Bagudo, Boal Bonifácio (or Vital or Malvasia Corada), Boal Barreiro, Boal Carrasquenho, Boal de Alicante, Boal Espinho and Boal Ratinho. The Bual grape is quite hardy and can withstand very hot temperatures and high winds. It ripens late in the season and can be prone to both powdery and downy mildews. It is usually blended with other varieties such as Malmsey and Verdelho to create fortified wines high in alcohol and sweetness. In Madeira, the Bual grape is used to make a medium-sweet to sweet, fortified wine. It has a deep yellow to amber colour and aromas of figs, raisins and butterscotch, nuts, caramel, toffee and orange peel. The sweet and nutty flavours of Bual wines make them a great accompaniment to a variety of desserts. They also pair well with salty and spicy foods, such as cured meats and cheeses.

Bual is also known by the name Boal.