He attended the Central National School in neighboring White Plains until 1936 when he enrolled in the High School division of Liberia College, graduating in 1941 with a Bachelor of Arts degree.
He entered public service in 1942 at the Department of State where he served as private secretary to Department Head Clarence L. Simpson, and chief of the Passport Division. In 1944 he was awarded a government scholarship to study at Howard University in Washington DC. He transferred after a year to the University of Michigan Ann Arbor, where in 1948 he earned a BSc and a Masters in Forestry.
Upon his return home he was employed at the Department of Agriculture and Commerce, where he organized the National Forestry Service and served as its first Director. In the same year he organized the University of Liberia School of Forestry, serving as its first Dean for twelve years.
In 1950 he became Secretary of Agriculture and Commerce, resigning in 1956 to devote his energies to private enterprise. Started with a Five Grand loan from his brother, The MESURADO FISHING COMPANY grew into the MESURADO GROUP OF COMPANIES, seventeen companies engaged in Import-Export, cold storage, frozen food development, acetylene and oxygen supply, soap manufacturing, wholesale and retail trading, (Swiss African Trading Co.) with branches in Nigeria, Sierra Leone, and England. The MG employed hundreds of Liberians and foreigners.
In 1960 Stephen A. Tolbert was recalled to public service as Secretary of Agriculture and Commerce. Among his many innovative proposals was the separation of the departments of Agriculture and Commerce. In 1964, he became Secretary of the new Department of Agriculture. In 1965 he again resigned and returned to running the MESURADO GROUP, achieving greater and greater success, and in 1972, his brother President William R. Tolbert Jr. appointed him Secretary of the Treasury, with the nomenclature changed to Minister of Finance. He suspended his active ties to the MESURADO GROUP in order to accept this assignment.
Tolbert represented Liberia abroad in a number of international organizations, was chairman of the Food and Agriculture Organization (FAO) Second Commission, Chairman of the Board of the Bank of Lagos, the Bank of Liberia, and was the first Board Chairman of LPMC, the Liberia Produce Marketing Company. LPMC was created on his recommendation. He headed the Liberian Chamber of Commerce, the Liberian Development Corporation Board of Directors, and that of the Liberian Bank for Development and Investment., LBDI, both of which he played a major role in creating. In 1974, in collaboration with the International Monetary Fund, he created the country's first central banking entity, the NATIONAL BANK OF LIBERIA, He was Vice Chairman in 1971 of the Advisory Board of the University of Liberia School of Business, and elected Chairman a year later, in 1972. He was the first Liberian to serve as Chairman of the Board of LAMCO, Vice Chairman of the Bong Mining Company Board of Directors, and Chairman of the Liberian Hotels Incorporated
As Finance Minister, Steve Tolbert focused his business acumen on the organizational needs of Liberian development. As Liberia Governor for the World Bank Group, the IMF and the African Development Bank, Tolbert structured a large flow of skills and capital into the Liberian economy. As Chairman of the Special Committee on Concessions Review, his negotiating skills led to substantial increases in national revenue. In his brief tenure as Minister of Finance from 1973-1975, revenue increased from $77.6M to $108.4M in 1974, and $111M in 1975.