The Lebanon Social Library was formed in 1802, offering between 300-400 books to the citizens of Lebanon. By 1889, it was known as the Lebanon Free Public Library, and was housed in the Grand Army Hall of the Soldiers Memorial Building, a stone's throw from the library's current location. At that time, it is estimated that the library contained several thousand items.
The Lebanon Public Library's present location was built in 1908 with $12,000 from private donations and an additional $12,500 grant from the Andrew Carnegie Foundation. The building was designed by the Boston architectural firm of McLean & Wright. A children's room was added to the basement of the building in 1958. An addition was added to accommodate the growing collection of books and materials in the 1980s. This addition which currently houses the children's, young adult, audiobook, and non-fiction collections, is named after former New Hampshire governor and Lebanon resident, the late Lane Dwinell.
The Lebanon Public Library now circulates over 40,000 items including books, magazines, audiobooks, e-book readers, Chromebooks, and museum passes.