Context/Objective: Graduate Medical Education (GME) contributes significantly to developing the physician workforce in the U.S. Family medicine (FM) residency programs are essential for the production of primary care physicians. Residency program locations are linked to physician distribution, particularly in the initial career stages. However, there are a lack of studies on how FM residency programs have grown historically. This study aims to review the FM residency program expansion in the U.S. for the last 40 years. Study Design: We collected residency program data from ACGME national reports over the five year interval from 1980 to 2019. We used program location zip code to define rural or urban status using USDA’s Rural Urban Continuum Codes. Additionally, state level aggregates were also tallied. The main outcome measures were the changes in the number of residency programs, total positions filled, and number of positions per 100,000 population. Results: Expected results show there were an increase of programs overall in the nation from 1980 to 2019. Furthermore, an overall increase of FM positions filled per 100,000 population is expected in the nation during the same period. However, we expect that most of the FM residency growth took place in urban areas. We further expect that there are significant interstate variations in FM residency growth over the years as every state emphasizes primary care differently. Conclusions: The study results should provide evidence to conclude whether FM programs expanded in proportion to population growth in the nation and whether FM residency programs significantly expanded toward rural areas where there are persistent shortages of primary care physicians. How family medicine residency programs expand may have significant implications for the nation’s future primary care physician workforce.