California is a leading producer of pistachios in the United States and globally and it is estimated that annual production will reach 2.08 billion pounds in 2031. As a result, about 31.2 million pounds of shells will be produced after the nuts are processed for human consumption. Pistachio shells have been viewed as a waste product and are frequently disposed of using ecologically friendly practices. However, it is possible that pistachio shell powder can be used as a high fiber ingredient for swine. Specifically, gestating sows may benefit from the high fiber concentration in pistachio shell powder because this may increase satiety and reduce stress. However, at this time, there is no information about the nutritional value of pistachio shell powder when fed to sows. Therefore, an experiment was conducted to test the hypothesis that apparent total tract digestibility (ATTD) of gross energy (GE) and concentrations of digestible energy (DE) and metabolizable energy (ME) in pistachio shell powder are not different from those in soybean hulls when fed to gestating sows. The second hypothesis was that the ATTD of GE and DE in pistachio shell powder are not different from those in soybean hulls when fed to lactating sows.