BTS Statistics — Air Carrier Traffic — T-100 Segment

Air Carrier Statistics: Domestic & International
Passenger Traffic, 2021–2025

Bureau of Transportation Statistics, Office of Airline Information

Published: March 13, 2026 Carriers: 32 U.S. reporting carriers Coverage: Jan 2021 – Dec 2025 Program: T-100 Segment

1. Industry Snapshot

Table 1.1
4.45 billion
Total Passengers Carried, All U.S. Carriers (2021–2025)
Enplaned revenue passengers, domestic and international scheduled service
32
Reporting Air Carriers
T-100 Segment, all carrier types
1.41M
Route-Month Records
Unique market-month combinations
5.57 billion
Total Available Seats
Scheduled capacity, all carriers
79.8%
System-Wide Load Factor (Period Average)
Revenue passengers / available seats
Key Finding
Over the 2021–2025 reporting period, U.S. air carriers collectively transported 4.45 billion passengers across 2,342 airport pairs. Monthly traffic consistently peaked in summer (July), with load factors reaching as high as 85.4% in July 2023. The four largest network carriers — Southwest, American, Delta, and United — collectively accounted for 70.7% of all passengers carried.[1]

2. Air Carrier Statistics, Ranked by Passengers

Table 2.1

Top 12 U.S. air carriers by total enplaned passengers, January 2021 – December 2025. Source: Bureau of Transportation Statistics, T-100 Segment Data.[1]

Table 2.1 — Carrier Traffic Summary (Top 12)
# Carrier Code Passengers Seats Departures Load Factor Routes Airports
Note: Passengers = total enplaned revenue passengers. Load factor = passengers / seats. Routes and airports reflect distinct T-100 segments served during the period.

3. Hub Airport Statistics, Ranked by Passengers

Table 3.1

Top 12 U.S. hub airports by enplaned passengers, January 2021 – December 2025. Includes all carriers serving each airport.[2]

Table 3.1 — Hub Airport Summary (Top 12)
# Airport Passengers Seats Load Factor Carriers Destinations
Note: Carrier count and destinations reflect distinct carriers and markets recorded in T-100 Segment data during the period. Excludes cargo-only operations.

4. Top City-Pair Routes, All Carriers

Table 4.1

Top 14 domestic city-pair routes by total passengers (both directions combined), January 2021 – December 2025. Includes all certificated air carriers.[1]

Table 4.1 — Top Routes by Passengers
# Route Passengers Load Factor Departures Carriers Top Carrier Top Share
Note: Route = bidirectional city pair. Top carrier share = proportion of all-carrier passengers carried by the largest single carrier on the route.

5. Monthly Traffic, All Carriers

Figure 5.1

Monthly enplaned passengers and available seats, January 2023 – December 2025. All U.S. certificated carriers combined.[3]

Figure 5.1 — Monthly Enplaned Passengers and Available Seats
January 2023 – December 2025   |   All U.S. Carriers   |   Millions
Passengers (millions)
Available Seats (millions)
i Chart Notes
Values represent monthly totals across all reporting carriers. Seasonality is evident: summer months (June–August) consistently show peak traffic; January–February reflect off-peak travel. Data points are plotted at mid-month; values are in millions of passengers or seats.

6. Load Factor Seasonality Heatmap

Figure 6.1

Monthly system load factor (revenue passengers / available seats) by year, January 2023 – December 2025. Darker blue indicates higher load factor.[3]

Figure 6.1 — System Load Factor by Month and Year
Percentage of available seats occupied by revenue passengers  ·  2023–2025
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Low
High Range: 74.4% – 85.4%
Seasonal Pattern
Summer months (June–August) show consistently the highest load factors across all three years, reflecting peak leisure and vacation travel demand. January and February register the lowest load factors each year, a pattern consistent with post-holiday demand trough. The July peak ranged from 83.1% (2025) to 85.4% (2023), indicating stable summer utilization even as capacity expanded year-over-year.

7. Methodology

§7
M Data Collection and Methodology

Data are collected under 14 CFR Part 241 from U.S. air carriers certificated under Part 121 of Federal Aviation Regulations. All carriers filing T-100 Segment forms are required to report monthly traffic and capacity statistics for each airport-pair segment served.

T-100 Segment Data captures origin-destination traffic at the airport pair level. Each record represents one carrier serving one airport-pair market in one calendar month. The dataset covers both domestic (U.S.–U.S.) and international (U.S.–foreign) scheduled service operations.

Load Factor is calculated as total revenue passengers divided by total available seats. Values are period totals aggregated from monthly reports. System-wide load factor represents the aggregate across all carriers and months.

Data Limitations: Figures exclude non-scheduled (charter) operations, cargo-only carriers not required to file T-100, and operations by foreign carriers. Regional carrier figures may be reported under their operating or code-sharing partner depending on the filing entity.

Citation
Bureau of Transportation Statistics. Air Carrier Statistics (Form 41 Traffic) — T-100 Segment (All Carriers). Washington, DC: U.S. Department of Transportation, 2026. Available at: transtats.bts.gov.

References

§Ref
  1. Bureau of Transportation Statistics. Air Carrier Statistics (Form 41 Traffic) — T-100 Segment (All Carriers). U.S. Department of Transportation. https://www.transtats.bts.gov/
  2. Bureau of Transportation Statistics. Airport Activity Statistics of Certificated Air Carriers. U.S. Department of Transportation. https://www.bts.gov/topics/airlines-and-airports/airport-activity-statistics
  3. Bureau of Transportation Statistics. Air Travel Consumer Report — Monthly Load Factor Summary. U.S. Department of Transportation. https://www.bts.gov/newsroom/air-travel-consumer-report

This page was generated from BTS T-100 Segment microdata. Last updated: March 13, 2026. For questions contact the BTS Office of Airline Information.