Playwright Marian de Forest and five other businesswomen founded the Zonta Club in Buffalo, New York, in 1919. Modeled after the men's executive club, Rotary, this women's executive club extended invitations only to the best women in their professions. Its focus was on networking and service.

In 1921, the Detroit, Michigan and Erie, Pennsylvania clubs joined the New York clubs, (Binghamton, Rochester, Elmira, Syracuse, Ithaca, Utica), found the Confederation of Zonta Clubs at the first convention in Syracuse. The first president of the Confederation was Mary Jenkins, a publisher of the Syracuse Herald. In 1930, the organization changed its name to Zonta International and elected Helen W. Cleveland as its first president.
During World War II, Zonta's service activities involved aiding their fellow Zontians through a War Service Fund, as well as cooperation with the Red Cross, sales of war stamps and bonds, and civil defense and first aid programs. In 1938, inspired by the death of Amelia Earhart, a member of the Zonta Club of Boston, Zonta established the Amelia Earhart Fellowship Awards for women pursuing advanced studies in aerospace-related science or engineering.
Zonta International has been engaging in women's development internationally and has taken an active part of assisting United Nations. Since 1959, Zonta has had consultative status with its agencies such as the International Labor Organization (ILO), United Nations Education, Scientific, and Cultural Organization (UNESCO), United Nations Development Fund for Women (UNIFEM), and the United Nations International Children's Emergency Fund (UNICEF). Zonta also maintains representatives at United Nations sites in Geneva, New York, Paris and Vienna.
On the local level, the Zonta Club of Buffalo undertakes projects addressing issues such as women's economic self-sufficiency, legislative equality, aging, access to education, health and nutrition. The Buffalo club cooperates with other groups within the Buffalo community for fundraising activities, promoting career exploration and providing community services for youth. In the past, the Buffalo club had collaborated with Erie County Commission on the Status of Women, Girl Scout Leadership Training Program, State University New York at Buffalo, Woman's Action Coalition, and the YMCA.

1919:

The Zonta Club was founded in Buffalo, New York.

1921:

The Confederation of Zonta Clubs was established; Mary Jenkins elected first president.

1922:

Zonta became incorporated, and its base of operation moved to Harriet Richards' home in Utica, New York.

1925:

Serbia honored Zonta for its service to the education of young Serbian women.

1926:

Zonta acquires its business office in the Women's Council Building of the Larkin Company of Buffalo, New York

1927:

Zonta became international as clubs on Toronto, Hamilton, and St. Catherines, Ontario joined the confederation.

1928:

Zonta headquarters moved to Chicago, Illinois.

1930:

The name of the organization changed to Zonta International; Helen W. Cleveland elected first president.

1932:

Headquarters moved to the Buckingham Building in Chicago.

1938:

Amelia Earhart Scholarships for Women established.

1954:

295 Zonta clubs in 13 foreign countries with 10,848 members.

1959:

First international service project with United Nations agencies.

1964:

427 Zonta clubs in 24 foreign countries with 17,500 members.

1979:

Zonta International moved to offices on 35 East Wacker Drive, Chicago.

1982:

Received an award from UNICEF for outstanding contribution to the children.

1986:

Zonta International purchased a building for its headquarters, 557 West Randolph Street, Chicago.

1994:

Buffalo club hosted Diamond Jubilee Celebration at Statler Towers, Buffalo, New York.

2007:

1,200 Zonta clubs in 67 countries with 33,000 members.