William Henefer's father, James Henefer Sr. (1791-1862), was a tinner, buckle maker, and iron monger. When William was seven years old, his mother, Charlotte Hicken Hennefer (1793-1832) died, and his father remarried around 1831 to Elizabeth Smith. In October 1840 two missionaries convinced William and his brother James Hennefer, that the gospel was true, and they were baptized in 1844. They immediately started to save for the trip to America. It took William four years to save enough. After his arrival in America, he obtained work in Trenton, New Jersey, where he met his future wife, Rebecca Ann Hays. They traveled to Council Bluffs where they joined a company of Saints going west. Upon their arrival, they found a home and William opened the first sanitary barbershop in Salt Lake City, known as Henefer’s Shaving Salon.
In the spring of 1853, William and his brother, James, were called to take their families to Henefer where they were to help the migrating Saints as much as possible by being blacksmiths and raising fresh produce.