Why are freight railroads separated into classes?

Separating the freight railroads into classes according to operating revenue helps with regulatory oversight

Union Pacific is a Class I railroad. (Photo: Jim Allen/FreightWaves)

U.S. freight railroads are usually identified as Class I, Class II or Class III. That can be helpful for several reasons.

The Surface Transportation Board (STB), an independent federal agency that oversees the economic regulation of freight railroads and deals with issues related to railroad rates and rail service, has divided the freight railroads into three categories based on their operating revenue. According to the American Short Line and Regional Railroad Association (ASLRRA), those categories are: 

  • Class I railroads: annual operating revenue over $489.9 million.
  • Class II railroads: annual operating revenue between $39.2 million and $489.9 million.
  • Class III railroads: annual operating revenue of less than $39.2 million.

Categorizing freight railroads into different classes is useful for regulatory reasons.

For instance, if a Class II railroad and a Class III railroad want to merge, they have fewer benchmarks to reach to gain regulatory approval from the STB than two Class I railroads seeking to merge. Because of their size, two Class I railroads must ensure that their operations and networks complement each other. The Federal Railroad Administration (FRA) may also want the two railroads to file safety integration plans.

Class I railroads are held to a higher regulatory standard. They must submit reports to STB detailing financial and operating statistics, including employment and traffic data. The board uses this information to produce monthly and quarterly employment reports, annual wage statistics of those railroads, and quarterly rail fuel surcharge reports. 

To learn more about what regulatory requirements Class I railroads must follow, go here.

Knowing what class a railroad falls under also helps stakeholders understand what government funding is available for infrastructure projects. 

According to FRA, the nearly $80 billion freight rail industry is made up of almost 140,000 route miles and consists of seven Class I railroads, 22 regional railroads and 584 short line railroads. The regional and short line railroads make up the Class II and Class III railroads.

Unlike other transportation industries, the major U.S. freight railroads are financially responsible for maintaining their own infrastructure.

Smaller railroad companies, such as the Class II railroads and Class III railroads, may be eligible for federal tax credits aimed at infrastructure improvements to help pay for maintenance, or they may take part in state or federal grants when working with public partners

Meanwhile, the larger railroads spend nearly $25 billion annually to maintain their networks and ensure there is enough capacity to handle all the volume that travels via their tracks, according to FRA. However, Class I railroads may also participate in state or federal grants if they work with partners that are eligible for government funding.

The railroad classes also serve as an unofficial shorthand for customers, local partners and government officials in understanding whom a freight railroad might serve. Class II and Class III railroads are known as short line or regional railroads that function as the first mile and last mile in a supply chain. They may serve rural communities or ports, and they connect or interchange with the larger Class I railroads. Some are family-owned and maintain close relationships with customers, whereas others may be part of a company that oversees several short line railroads across the U.S. and Canada. The length of their networks can also be short: Class III railroads have a median length of haul of 15 miles, according to ASLRRA.

In contrast, the networks of Class I railroads span thousands of miles across several states, and their volume capacity is much greater than those of the Class II and III railroads. Their public nature — six of the seven Class I railroads are publicly traded — also enables them to be more visible proponents — or targets — of issues that might affect the freight rail industry as a whole.

Subscribe to FreightWaves’ e-newsletters and get the latest insights on freight right in your inbox.

Click here for more FreightWaves articles by Joanna Marsh.

Upcoming FreightWaves Events
Compliance

Brokerage Compliance Symposium

The day before F3. Every compliance issue you face - fraud exposure, carrier liability, FMCSA rules, cargo theft, insurance gaps - navigated by attorneys and operators defining best practices in a changing industry.

October 26, 2026
The Signal at Chattanooga Choo Choo • Chattanooga, TN
Register Now
Awards

F3 Awards Dinner

The night before F3. FreightTech100 companies honored. FreightTech 25 and Shipper of Choice winners revealed live. Cocktail reception into dinner and live music - 300 industry leaders in one purpose-built room.

October 26, 2026
The Signal at Chattanooga Choo Choo • Chattanooga, TN
Register Now
FreightTech

F3: Future of Freight Festival

Industry-defining keynotes, rapid-fire technology demos, and industry leaders networking in experiences across Chattanooga - plus the inaugural F3 Awards Dinner featuring the FreightTech and Shipper of Choice reveals.

October 27, 2026 – October 28, 2026
The Signal at Chattanooga Choo Choo • Chattanooga, TN
Register Now
Compliance Brokerage Compliance Symposium Oct 26 • The Signal at Chattanooga Choo Choo • Chattanooga, TN

The day before F3. Every compliance issue you face - fraud exposure, carrier liability, FMCSA rules, cargo theft, insurance gaps - navigated by attorneys and operators defining best practices in a changing industry.

The Signal at Chattanooga Choo Choo • Chattanooga, TN Register Now
Awards F3 Awards Dinner Oct 26 • The Signal at Chattanooga Choo Choo • Chattanooga, TN

The night before F3. FreightTech100 companies honored. FreightTech 25 and Shipper of Choice winners revealed live. Cocktail reception into dinner and live music - 300 industry leaders in one purpose-built room.

The Signal at Chattanooga Choo Choo • Chattanooga, TN Register Now
FreightTech F3: Future of Freight Festival Oct 27 – Oct 28 • The Signal at Chattanooga Choo Choo • Chattanooga, TN

Industry-defining keynotes, rapid-fire technology demos, and industry leaders networking in experiences across Chattanooga - plus the inaugural F3 Awards Dinner featuring the FreightTech and Shipper of Choice reveals.

The Signal at Chattanooga Choo Choo • Chattanooga, TN Register Now

Joanna Marsh

Joanna is a Washington, DC-based writer covering the freight railroad industry. She has worked for Argus Media as a contributing reporter for Argus Rail Business and as a market reporter for Argus Coal Daily.