According to the original bylaws, the day-to-day operations of the Society were to be paid for in part by donations of two dollars (later changed to six) per year per member. This system does not appear to have been effective, and, in treasurers' reports from 1830 on, there was no mention of dues or levies for members.
After the death of Thomas in 1831, funding for operating expenses was derived mainly from the income from his bequest, which had established a fund that was deemed adequate for the Society to be self-sustaining. Although the income was modest, so were the expenses. In 1854, the Society operated on a budget of $1,300.
The first formal appeal to members for voluntary annual support was made in 1934 when Clarence S. Brigham, badly shaken by the deaths of two of the Society's staunchest members, Waldo Lincoln and Calvin Coolidge, upon whom he had depended to aid him in raising capital, decided that, without an adequate endowment, he must depend on annual gifts from members. Today, contributions to the Society's annual fund come from members, friends, corporations and foundations.
Individual donors to the annual fund become members of the Alliance for the American Antiquarian Society, a three-level friends organization initiated in 1989 to invite broad participation in the activities of AAS. The three groups are Friends (contributing $50 or more annually), the Worcester Association of Mutual Aid in Detecting Thieves ($200 and over), and the Isaiah Thomas Society ($1,000 and over). The Thief Detectors have supported the Society since 1978, when members of the Society took the name and legal status of a moribund local social club that had evolved from a citizens' police force dating to 1795. The Alliance now has almost six hundred members whose contributions provide vital general operating support.
- Mary V.C. Callahan, former Development Officer, and Lynnette P. Sodha, former Director of Development; updated by John M. Keenum, Vice President for Development.