Santo Wines, the Union of Santorini Cooperatives, was founded in 1947 and is committed not only to producing high quality wine but also to protecting the Santorini vineyard. Its role in the promotion of Santorini wine is of decisive importance, as it produces large quantities of wine and has helped many wine producers at their first steps. All the wine producers of the island are members of it.

It is located at Pyrgos, overlooking the caldera. They cultivate 1200 hectares of vine, in close collaboration with all the producers, whom they also advise on the ways their wines could be improved. They produce several types of wine of different colors and dryness. The most important are: