Billikopf had a long and distinguished career in public service work. He served as the superintendent of the United Jewish Charities in Milwaukee, Wisconsin and Kansas City, Missouri, before becoming the executive director of the Federation of Jewish Philanthropies in Philadelphia, Pennsylvania, chairman of the National Labor Board for the Philadelphia region during the first years of the new deal.
In 1907, Billikopf moved on to Kansas City, Missouri, where he became superintendent of the United Jewish Charities, while contributing to the establishment of public baths, night schools, a municipal loan agency, and free public legal aid.
In 1914, the NAACP recruited Billikopf and other Jewish leaders for its board.
In 1916, Billikopf was elected President of the National Association of Jewish Workers
In 1917, Billikopf left Kansas City and came to New York City where he became the executive director of the American Jewish Relief Committee which raised $20M for the aid of displaced European Jews after World War I