Accessing Airports: Available Public Transit Options and Efforts to Promote Their Use

What GAO Found

Of the 51 large, medium, and small airports included in GAO's review, all but two small airports have some level of public transit service by bus or rail. Accessing airports by transit, instead of driving or taking taxis or rideshares, can help reduce congestion on increasingly busy airport roads. GAO found that 23 of the nation's 31 large airports have rail service such as light or commuter rail. For 18 of these airports, the rail service is either located on airport grounds or off-site but connected by an air train that moves passengers on dedicated tracks. The remaining five large airports have rail service located off the airport grounds but connected by a free bus. The 20 selected medium and small airports generally have bus service from the airport curb to the local downtown.

Large Hub Airports with Transit Rail Service (such as light or commuter rail)

Note: Includes large hub airports per Federal Aviation Administration 2023 passenger boarding (enplanement) data.

Use of transit by passengers and airport and airline employees varies widely across airports. Transit use ranged from 4 percent to 19 percent for the 12 airports for which GAO identified reports on passengers' mode of transport. For employees, two large airports GAO visited reported that 17 percent and 19 percent of surveyed employees used public transit. Meanwhile an estimated 4 percent of airport and airline employees nationwide used public transit to commute, according to GAO's analysis of Census data. Factors that influence individuals' transit decisions include cost, travel time, and familiarity with transit options, according to Transit Cooperative Research Program reports and stakeholders GAO interviewed. In addition, people with disability consider factors such as availability of elevators or accomodations for mobility aids. Employees may also consider the availability of parking or transit benefits and transportation modes that match their work shifts, which often begin early in the morning.

Some airports have begun to implement transportation demand management (TDM) strategies to promote the use of existing transit options. TDM broadly refers to efforts to reduce congestion and vehicle-related emissions. Five airports GAO visited were implementing TDM strategies, such as additional signage or advertising of transit options, or offering incentives, such as reduced cost transit. Although airports are implementing TDM strategies for passengers and employees, some are prioritizing strategies for employees who may be more willing to shift to transit due to their familiarity with the airport. Two airports GAO visited set, and plan to assess, transit use goals for their TDM strategies.

Why GAO Did This Study

Millions of passengers and employees travel to and from U.S. airports daily. Increased air travel demand has renewed concerns about congestion on roads to airports. Some airports and transit agencies have implemented TDM strategies to increase transit capacity or the use of existing transit to relieve congestion.

The Federal Aviation Admministration (FAA) Reauthorization Act of 2024 includes provisions for GAO to assess the extent to which U.S. commercial airports are accessible by transit and the TDM strategies that airports are implementing.

This report addresses, among other things, (1) public transit availability at selected U.S. airports; (2) passenger and employee use of public transit to access airports and the factors that influence their decisions to do so; and (3) TDM strategies selected large airports are implementing and plans by the airports to assess the effects of these strategies.

GAO reviewed airport websites and conducted literature searches to identify documentation on transit options and use for 51 airports-all 31 large-hub airports and a random selection of 20 medium-hub and small-hub airports based on 2023 FAA enplanement data. GAO contacted all 51 airports to confirm this information was accurate. GAO also analyzed 2019-2023 Census data on employee commutes. GAO reviewed Department of Transportation (DOT) guidance and interviewed officials from DOT and nine stakeholder organizations selected to represent a range of perspectives. GAO visited five large airports that recently implemented projects to increase transit capacity, were implementing TDM strategies, or both. At each airport, GAO interviewed airport and transit agency officials and other stakeholders.

For more information, contact Andrew Von Ah at [email protected].