Born in Troy, New York State, as Sarah Wilkinson, in 1903, following her father's death, her two younger brothers were made executors of his will. In 1904 Solano ran away from home and married Oliver Filley, an engineer. They spent the next four years in the Philippines, China, and Japan, but Solano left the marriage, returning to New York in 1908.

After an attempt to earn money in the theatre, Solano moved to Boston where she becme a successful journalist. In 1918 she moved back to New York to be theatre critic for the New Yorker Tribune. In the winter 1919 Solano met and fell in love with Janet Flanner and together the two women moved to Europe where they traveled widely.

Her partner Flanner's work as the Paris correspondent for the New Yorker meant that Solano incresingly worked for Flanner, doing background research and writing up her notes. They cntinued to work together through their lives. Wile Solano's and Flanner's relationship continued, the latter especially became repeatedly deeply involved with other women.

In the 1940s Solano eventually met and fell in love with Elizabeth (Liz) Jenks Clark. They moved together, first to the US, and then after the WWII to Orgeval in France, to look after the singer Noel Haskins Murphy, one of Flanner's great loves. Solano and Flanners had a large circle of lesbian friends throughout their lives and never abandned each other.