It is now common for transit operators to provide real-time information (RTI) to passengers about the location or predicted arrival times of transit vehicles. The Metropolitan Transportation Authority (MTA) in New York City has recently made RTI available for most of the subway, which is the largest urban heavy rail system in the United States. In light of this, the objective of this research is to investigate how RTI is likely to impact subway passengers in New York City. The method is a two-part literature review of prior studies that assess the passenger benefits of providing RTI. The first part compiles literature for all transit modes to identify which passenger impacts of RTI are found in multiple studies. In total, twenty-eight studies were reviewed, and five key passenger benefits were identified. The second part includes a more detailed review of prior studies conducted in urban heavy rail systems (six in total), which are most likely to be applicable to the New York City Subway. The results of the first part of the literature review suggest that the five most common impacts associated with providing RTI to passengers pertain to (1) decreased wait times, (2) reductions in overall travel time due to changes in route choice, and (3) increased use of transit. RTI may also be associated with (4) increased satisfaction with transit service and (5) increases in the perception of personal security when riding transit. The prior studies of urban heavy rail systems reveal that the most likely passenger impacts are decreased wait times (three of six studies), decreases in overall travel times (one study), and increased transit use (three studies). Therefore, it is recommended that future research focus on these three areas to evaluate the impacts of RTI on New York City Subway passengers.