Airport Roles According to NPIAS

The NPIAS is updated and published by the FAA every two years. This report uses predetermined evaluation criteria to identify airports that are of national importance to the air transportation system and inclusion in the NPIAS makes an airport eligible for AIP funding. The evaluation criteria consider important airport metrics such as commercial service enplanements, proximity to other airports and the number of based aircraft at an airport, making the NPIAS an excellent resource when understanding the role of the airport. Identifying if an airport is included in the NPIAS, followed by determining its classification within the NPIAS, provides insight into what role an airport plays within the larger regional and national aviation context.

As of January 2016, there are over 19,300 aviation facilities in the United States. However, almost three-quarters of these facilities are for private use only and not open to the general public, and therefore not eligible for the NPIAS. Of the roughly 5,100 remaining eligible public-use airports and other aviation facilities, over 3,300 airports, heliports, and seaplane bases are identified in the most recent NPIAS. A majority of the airports in the NPIAS are publicly owned, while a small number of airports are privately owned, but open for public use, and therefore also included in the plan. To learn more about the criteria used to classify NPIAS airports see the Changing NPIAS Classification section.

The NPIAS airports are generally categorized as either primary (commercial service) or nonprimary (GA) airports based on the number of commercial service enplanements, number of based aircraft, location or proximity to other airports, or a combination of the three. All primary and commercial service airports are in the NPIAS, while only select GA airports are included. Although most of the annual enplanements occur at primary airports, these airports account for only a small portion of the overall airports in the NPIAS. Out of the over 3,300 NPIAS airports, just less than 400 airports are considered primary. The remainder of the airports are nonprimary and mainly serve GA aircraft. Due to the large number of airports classified as GA, the FAA in 2012 and 2014 developed two additional reports to further classify these airports. See General Aviation Airports: National Assets for further information.

Click below to read about each category of NPIAS airports:

  • Primary Airports
  • Airports are included in this category based on their role as commercial service airports. Less than 15 percent of the airports in the NPIAS are primary airports. To be included in this category the airport must be a public-use airport with scheduled commercial airline service and have more than 10,000 annual passenger enplanements. Primary airports are further broken into four subcategories of large, medium, small, and nonhub airports based on the percentage of enplanements an airport has each year as compared to the total national enplanements.

  • Nonprimary Airports
  • A majority of the NPIAS airports fall into the nonprimary category. Airports considered and classified with this designation are mostly used for GA aircraft operations. There are three service levels of non-primary airports: nonprimary commercial service, reliever airports and GA airports. Nonprimary commercial service airports mostly serve GA aircraft, but do have limited commercial service as the name implies. Reliever airports are often found in large metropolitan areas, and provide additional regional capacity where nearby airports primarily serve larger commercial air service aircraft. The last service level, GA airports, is the largest segment of the NPIAS airports.



    The NPIAS report identifies over 3,300 public-use airports that are of significance to the national air transportation system. The NPIAS narrative provides a chart showing the breakdown of NPIAS airports. Appendix B: State and Territory Maps of NPIAS Airports includes national and state maps of NPIAS airports.

  • Field Formulation of the NPIAS

    This FAA Order (Order 5090.3C) provides guidance and sets forth policies and procedures for the continuous formulation, maintenance, and periodic publication of the NPIAS.