Thomas Nason was born in Massachusetts and grew up on a farm, where he had the opportunity to observe all forms of nature. Nason showed early talent at drawing, but the only formal study he received was a life-drawing course he took in 1916-1917.

Nason's first jobs were clerical, mainly as secretary to individuals who traveled widely. In 1917, Nason enlisted in the Eighth Massachusetts Regiment and served six months in France. He continued his self-education by familiarizing himself with the print departments in neighborhood bookstores and became friends with Percy Grassby, a wood engraver whom he accompanied on sketching trips. By 1921, Nason had produced his first woodcuts and progressed to wood engraving. He acquired a small hand press and worked in a room in his house. In 1923, his artistic reputation was established when he sold six woodcuts to Century Magazine. During the next few years, his prints were sold by bookstores and art dealers in Boston and New York.

Nason continued secretarial work until 1931, when his employer died; at that time he decided to devote himself full-time to his art. Nason earned a living from a series of commissions for bookplates, and from magazine and book illustrations, such as Robert Frost's You Came Too. Over the course of his career Nason produced more than six hundred prints.  

Nason was elected to the National Academy of Design in 1936. He was a member and fellow of the American Academy of Arts and Sciences, a member of the National Academy, the National Institute of Arts and Letters and the Lyme Art Association.