Waite had a twin brother, Wiate, who died at nineteen. Waite would use his oil rights to form the Waite Phillips Petroleum Co, but mainly got involved in real estate and banking after selling off his company around 1925.
In Tulsa, Oklahoma, he built several office complexes, such as the Philtower and Philcade, as well as his mansion, the Italian Renaissance-style Villa Philbrook. He would later donate his immense house to the city of Tulsa, where it was transformed into the Philbrook Museum of Art. All these buildings are on the National Register of Historic Places.
Interested in ranching, and in having a ranch with recreational activities, he began purchasing land in northern New Mexico near Cimarron. He built a mansion there called Villa Philmonte. His great-grandchildren occasionally vacation to this area. A restless soul, he would later donate about a third of the ranch to the Boy Scouts of America to found Philturn Rocky Mountain Scout Camp. Later, the name was changed to Philmont Scout Ranch. He also donated the Philtower Building to the Boy Scouts to financially support Philmont Ranch. He contributed substantially to the University of Southern California as well and the Waite Phillips Hall of Education was named in his honor in 1966.
Upon his wife Genevive's death on June 19, 1979, the bulk of the remaining estate was also donated to educational and medical charities. Mr. and Mrs. Phillips are buried in Westwood Village Memorial Park Cemetery in Los Angeles, California.
He also owned a stretch of land in California, that was later developed into Rodeo Drive, known for its upper-class shopping. He was also the builder of what later became known as the "Robert Taylor Ranch."