Teacup pigs are not real. The term teacup is a marketing ploy to sell piglets, but they reach the size of medium or large dogs when they become adults.
Teacup pigs are also known as "mini," "pocket" or "micro" pigs. There is no pig breed that remains small despite attempts by hog breeders to make smaller pigs. The only pigs that are more miniature than normal are deformed or malnourished ones. Teacup pigs can weigh anywhere from 60 to 95 pounds as adults, but others can weigh more than 100 pounds. Pigs can reach full maturity in five years, and many so-called teacup pigs are abandoned by owners because of their large size. This is the result of breeders who tell buyers that the piglets remain small throughout their lives.