The League of Women Voters (LWV), a national membership organization works on the national, state, and community levels of government to promote political responsibility through informed and active participation of citizens in their government. The League takes action in support of or in opposition to selected governmental issues, but it does not support or oppose candidates nor support or oppose political parties. Nonpartisanship is an established policy. A citizen eighteen or older joins at the local level and works through the local League on the three levels beginning with community government. In 1974 membership was opened to men. On February 14, 1920, Carrie Chapman Catt, president of the National American Woman Suffrage Association, at its six-months-premature victory celebration of the upcoming ratification of the 19th Amendment at convention in Chicago, spearheaded the founding of the LWV as a way to educate newly franchised voters.

Montana women had been granted the vote in 1914 and were eager to join the League. The first Montana League organization meeting was held in Great Falls on April 26, 1920, where plans were made to establish bylaws for the regional convention. This convention was held in Butte on May 25, 1921, and Mrs. A.F. Rice of Butte was elected president. The first convention established the objectives and policies of the Montana League of Women Voters to work toward efficient government, the good of public welfare in government, and international cooperation to prevent war. The League declared that it would not align itself with any political party but that it could endorse measures and policies. The League also declared that it would urge every woman to become a registered voter. Early Montana League members included Jeannette Rankin, Maggie Smith Hathaway, Frieda Fligelman, Belle Fligelman Winestine, and Dr. Mary B. Atwater.

The Montana League was a loosely structured organization in the state during the early 1920s and 1930s with the members meeting in Helena during the legislative sessions. The League was inactive during the World War II years. After 1946 the League of Women Voters of the United States (LWVUS) provided funds from the Carrie Chapman Catt Trust to employ an organizing secretary who would work to organize local and state Leagues in six western states. Irene Sweeney, national organizer, came to Montana to organize local Leagues in six selected communities. By 1952 local Leagues were established in Billings, Butte, Great Falls, Havre, Helena, and Missoula. The next step was to bring these local Leagues into a state organization. In 1953 a meeting of 29 delegates was held in Helena, and Laura Nicholson, a Helena member, was elected to begin the organizational work. The State Organization Committee coordinated a program of study of state government, with each local League investigating some phase of government. In April 1955 the first state convention was held in Butte. Catherine Jones of Missoula was elected first state president, an agenda was adopted, a budget prepared, and the LWVMT has continued under this format ever since. The LWVMT brings together the local Montana Leagues and works at the state government level.

In 1988 there were eight local Leagues; Billings, Bozeman, Flathead County (Kalispell, Whitefish), Great Falls, Liberty County (Chester), Helena, Missoula, and Ravalli County (Hamilton). Interested citizens who live outside established local Leagues may join as members-at-large (MALS) and they become the responsibility of the state board. Several local Leagues which have dissolved continue their members in MAL status including Butte, Miles City, and Havre. LWVMT is financed by local Leagues' per-member payments set by the state Board of Directors. Officers and Board members are elected at its biennial convention. In 1987 for the first time LWVMT hired a paid lobbyist, funded by contributions from members.

The LWVUS works at the national level of government, supporting and opposing issues on which a grass roots position has been taken. There are Leagues in all fifty states, the District of Columbia, Puerto Rico, the Virgin Islands, and Hong Kong. Headquarters for the national elected officers and Board of Directors is in Washington, D.C. Officers and Board members receive no salary. The LWVUS is financed by membership dues and contributions from members and interested public citizens. The League of Women Voters Education Fund (LWVEF) is a separate educational arm, responsible for raising funds to enable the LWVUS to carry on its program of work in the field of political activity. LWVEF has a paid professional staff, researches the critical political, social, and economic issues, and prepares educational materials for wide distribution. The League works on governmental issues chosen by the membership. Six months before the biennial national convention, local Leagues begin a discussion of issues and send in recommendations for the national program. The national Board considers these issues and sends a "Proposed Program" to Leagues for a second round of discussion. Final decisions are made by majority vote of delegates in convention. State and local programs are selected by the same general democratic procedure as in the national program. The program is divided into two parts: current agenda, issues selected for concentrated study and concerted action (such as environmental quality or welfare reform); and continuing responsibilities, positions on issues to which the League has given sustained attention and on which it may continue to take action (such as land use or voting rights). Position statements formed through the process of discussion and consensus at the local unit meetings are summarized, printed, and made available to members who may use them to lobby at the local government level. Position statements adopted by the LWVMT are summarized and published in the group's handbook. Topics of concern to the LWVMT in the past have included Montana institutions, executive reorganization, and constitutional revision. LWVMT members and officers may serve as volunteer lobbyists during the legislative sessions. All local and state Leagues are active in Voters Service, publish factual information on issues, conduct candidates meetings, register voters, hold candidates debates, monitor polling places, and work to get out the vote.