Not all US air routes are competitive. The US airline market has consolidated substantially since 2005, when there were a dozen major carriers and the competitive pressure kept fares lower even on thin routes. Today, with four carriers controlling roughly 80 percent of domestic capacity, specific markets have settled into a pattern of structurally elevated fares with little pressure to bring them down. These are not temporary pricing anomalies. They are the predictable outcome of a market where one or two carriers dominate a route and no low-cost competitor has found it worthwhile to enter.

This analysis identifies how airfare gouging works structurally, which types of routes are most affected, and what, if anything, you can do about it.

How to Measure Airfare Gouging: The Metrics That Matter

Base fare is a misleading comparison metric on its own because routes vary in length. A $400 fare on a 2,500-mile transcontinental flight is reasonable. A $400 fare on a 300-mile regional hop is not. The right metric is cost per mile, which normalizes fares by distance and makes disparate routes comparable.

The Bureau of Transportation Statistics (BTS) tracks average yield (revenue per passenger mile) by route and carrier through its quarterly Origin and Destination Survey. The national average domestic yield for US carriers runs in the range of 14 to 18 cents per mile depending on season and route length. Long-haul routes typically have lower per-mile costs due to fixed cost spreading; short-haul routes tend to be more expensive per mile even in competitive markets.

The second metric is competition index: the number of carriers offering nonstop or one-stop service on a given route. Routes with a single nonstop carrier and no viable one-stop alternative at a reasonable price are the most captive markets. Routes with two or more nonstop carriers competing are generally more fairly priced.

A route qualifies as structurally elevated in this analysis when: the per-mile cost exceeds 30 cents (roughly double the national average), fewer than two carriers offer meaningful service, and there is no low-cost carrier nonstop on the route.

Small City Routes: The Monopoly Market Problem

The most extreme cases of airfare pricing above competitive norms occur in small and medium markets that are served by a single regional carrier. These are cities where the volume of traffic does not attract multiple carriers, where a single regional airline operates under a capacity purchase agreement with a legacy carrier, and where the economics of the route essentially guarantee elevated fares.

Cities like Billings, Montana (BIL); Bismarck, North Dakota (BIS); Cheyenne, Wyoming (CYS); Traverse City, Michigan (TVC); and dozens of similar markets share a structural characteristic: one regional carrier, operating regional jets, connecting the city to a hub with no nonstop alternatives. The per-mile fares on these routes are frequently in the 40 to 80 cent range, three to five times the national average.

A round-trip fare from Billings to Denver or from Bismarck to Minneapolis on a 500-mile route can easily run $400 to $600, pricing that would be considered expensive on a coast-to-coast flight four times as long. These are not market anomalies. They are the going rate, and they have been for years.

The driving economics: regional jets carrying 50 to 76 passengers have significantly higher per-seat operating costs than mainline narrowbody aircraft. The fixed costs of operating any commercial flight, including crew, ATC fees, ground handling, and airport costs, are spread over fewer seats. Combined with no competitive pressure, the result is structurally high fares.

Hub Captive Markets: When the Hub Wins

A different type of fare elevation occurs in markets where a legacy carrier dominates a hub so thoroughly that routing alternatives require an impractical detour. These are not small cities; they can be mid-sized markets with meaningful travel demand. The problem is that one carrier controls the hub to such a degree that flying through a competing hub adds two to four hours of travel time, which effectively eliminates the competitive alternative for most travelers.

Charlotte Douglas (CLT) is the most cited example. American Airlines has over 90 percent of nonstop departures at Charlotte, making it one of the most hub-concentrated airports in the US. For travelers at Charlotte-area airports, American's fares face essentially no competition from other major carriers on most routes. The result: Charlotte frequently appears in BTS data as a market with elevated average fares relative to comparable-distance routes at more competitive airports.

Similar dynamics apply at Newark (EWR), where United's dominance in the New York area's third airport gives it pricing power that JFK and LaGuardia's more competitive environments limit for American, Delta, and JetBlue. Fort Worth's DFW has American's hub concentration, though the size and breadth of the market means competition exists across more routes than at a smaller hub like Charlotte.

The specific routes within hub-captive markets that show the most elevated fares are shorter-haul connections from the hub to secondary cities that have no alternative routing. A flight from Charlotte to Raleigh-Durham, or from Charlotte to Greenville-Spartanburg, at under 200 miles may price at $200 to $350 round trip on American with no competitive alternative nonstop, representing per-mile costs that dwarf any reasonable benchmark.

High-Fare US Regional Markets: Structural Examples

Several city pairs and market types have shown persistently elevated fares in BTS data over multiple years:

Island routes: Flights to Hawaii from the West Coast are competitive due to multiple carriers. But flights to smaller islands, including inter-island Hawaii routes not served by Hawaiian Airlines' now-restructured network, and routes to US territories like Guam (GUM) from the continental US, can be significantly elevated. Guam is served by a very limited number of carriers on transpacific routes, making it one of the more expensive per-mile options in the US system.

Mountain West secondary markets: Aspen (ASE), Sun Valley/Hailey (SUN), Jackson Hole (JAC), and Telluride (TEX) are all airports where the combination of limited runway capacity (Aspen's high-altitude single runway turns away many aircraft types), seasonal demand concentration, and wealthy traveler demographics results in extremely high fares. Aspen to Denver on a 200-mile route regularly prices at $300 to $600 round trip, with per-mile costs in the top tier of any US route pair. The justification, to the extent any exists, is the limited aircraft types that can operate Aspen approaches and the short ski season that must generate annual revenue in a compressed window.

Nantucket (ACK) and Martha's Vineyard (MVY): These seasonal New England island destinations see extremely high fares during summer months when demand peaks, operated by Cape Air and other regional operators with small turboprop aircraft. The economics are similar to mountain West resort airports: small aircraft, limited operations, high seasonal demand concentration. Nantucket to Boston on a 90-mile flight has historically priced at $150 to $400 each way in peak season.

The Role of Regional Jets: Why Small Aircraft Mean High Fares

The cost economics of regional jet operations explain much of the per-mile premium on small-city routes. A 50-seat Bombardier CRJ-200 or 76-seat Embraer 175 costs significantly more per seat-mile to operate than a Boeing 737 or Airbus A320 carrying 150 to 185 passengers. The reasons are mechanical: more fixed costs spread over fewer seats, higher fuel cost per seat due to smaller engines optimized for shorter routes, and crew costs that do not scale linearly with aircraft size.

When a regional carrier operating under a capacity purchase agreement with a legacy airline fills a 76-seat regional jet on a 400-mile route, the per-seat operating cost is substantially higher than what a mainline 150-seat narrowbody would cost on the same route. The legacy airline that controls the route pricing sets fares accordingly to cover those costs plus margin. Travelers on these routes are paying a structural premium that has nothing to do with demand and everything to do with aircraft economics.

The solution, when it exists at all, is mainline service. If a route grows enough to support mainline aircraft, the legacy carrier can shift to larger planes with lower per-seat costs and, sometimes, introduce more competitive pricing. But routes that plateau below the threshold for mainline economics stay in the regional jet penalty zone indefinitely.

What Drives Change: New Entrants and the Southwest Effect

The most powerful force for fare reduction in captive markets is carrier entry. The Southwest Effect, named for the consistent pattern of fare reduction when Southwest enters a new route, is one of the most well-documented phenomena in airline economics. When Southwest began serving Baltimore-Washington, fares at that airport dropped substantially. When Southwest entered markets like Cleveland, Providence, and Long Island MacArthur, similar fare reductions followed as existing carriers responded to the competitive threat.

The same effect applies to any low-cost carrier entry. When Spirit or Frontier entered a route previously dominated by a single legacy carrier, fares dropped, sometimes dramatically, within months. The inverse is also true: when Spirit exited routes following its bankruptcy network contraction in 2024 and 2025, fares in those markets increased. Academic research has quantified the Spirit Effect as a 10 to 20 percent average fare reduction in markets where Spirit competed.

Spirit's post-bankruptcy route exits have therefore directly contributed to fare increases in some markets that previously had ultra-low-cost competition. This is not coincidence; it is the predictable consequence of reduced competition.

For new entrant competition to reach truly captive small-city markets, the economics would need to support operating regional-scale aircraft on those routes. No ultra-low-cost carrier has made this work at scale, because the same per-seat economics that drive high fares at legacy carriers also apply to any carrier using small aircraft on thin routes.

What You Can Do as a Traveler

The options for travelers in captive markets are genuinely limited, but they exist:

Drive to a larger airport: If you are two to three hours from a more competitive airport, the math often favors driving. A traveler in Billings who drives to Great Falls or Bozeman, or flies from a different regional airport that has more carrier options, may find significantly lower fares that offset the additional travel time. This requires flexibility and planning, but on expensive small-city routes, the savings can be $200 to $400 per round trip.

Consider ground alternatives for short haul: On routes under 300 miles, Amtrak, intercity bus, or driving are worth genuine comparison. A Nantucket to Boston trip that costs $200 each way by air is worth comparing to the ferry and a weekend car trip, depending on circumstances. Ground transport's time disadvantage shrinks significantly on very short routes when airport time is factored in.

Book far in advance: In captive markets with limited seat counts on small regional jets, booking early provides some pricing advantage. Fares in these markets tend to increase as the departure date approaches and remaining seats become scarcer. Booking 4 to 8 weeks out consistently captures lower fares than booking inside two weeks on small-city routes.

Check all nearby airport options: The relevant comparison is not just the captive route but all airport combinations that could get you to your destination. Search on Farefinda with flexible origin and destination settings to see all carrier and routing combinations, including one-stop itineraries through alternative hubs that might price below the captive nonstop fare.

Flexible date search: Even in captive markets, fares vary by day of week and time of year. Flying midweek or in shoulder season can produce meaningful savings relative to the peak weekend fares that reflect concentrated demand. The captive market premium shrinks somewhat when demand is lower and carriers have empty seats to fill.

The Regulatory Picture

The DOT has authority over certain airline practices but does not regulate fare levels on competitive routes. The Essential Air Service (EAS) program subsidizes service to some remote communities, but the subsidy covers operating costs rather than fare levels, and EAS communities often still pay elevated fares even with subsidized service in place.

Antitrust oversight of airline mergers has become more active since 2022, with the DOT and DOJ successfully blocking the American-JetBlue Northeast Alliance and the Spirit-JetBlue merger. These decisions have kept JetBlue as an independent competitive force in Northeast markets where it had been a meaningful fare competitor. But structural consolidation in the industry remains, and the competitive dynamics in small-city markets are unlikely to change significantly without either new entrant competition (which the economics do not support at scale) or regulatory intervention in fare levels (which does not currently exist).

Frequently Asked Questions

Why is my small-city flight so expensive?

The primary reasons are small aircraft economics and limited competition. Regional jets carrying 50 to 76 passengers cost significantly more per seat to operate than larger mainline aircraft. When a single regional carrier dominates a route and faces no competitive pressure, it prices to cover those costs plus margin. The result is per-mile fares two to five times the national average. This is not price gouging in the legal sense; it reflects genuine cost economics combined with an absence of competition.

Can anything actually be done about route monopolies?

In practice, the most effective solution is new carrier entry. When a low-cost carrier enters a captive market, fares drop immediately and sometimes dramatically. The challenge is that small-city markets often cannot support the economics of low-cost carrier operation, which is why they remain captive. Regulatory options are limited; the DOT does not set fare ceilings on competitive routes, and the Essential Air Service program addresses access but not pricing. For most captive markets, the realistic options for travelers are driving to a larger airport, searching for alternative routings, or paying the prevailing fare.

Does filing a complaint with the DOT help with high fares?

Filing a complaint with the DOT Aviation Consumer Protection Division is appropriate for violations of consumer protection regulations: denied boarding without compensation, refund delays, or deceptive fee disclosures. It is not an effective tool for addressing elevated market fares, which are not a regulatory violation if the carrier is not engaging in illegal coordination. If you believe carriers are colluding on prices rather than independently pricing to market conditions, a complaint to the DOJ Antitrust Division is the more relevant avenue, though enforcement actions are rare and slow.

Which US routes have the highest fares per mile?

BTS Origin and Destination Survey data consistently shows the highest per-mile fares on routes including small-city regional connections (Billings to Denver, Bismarck to Minneapolis, Traverse City to Chicago), resort market routes (Aspen to Denver, Jackson Hole to Salt Lake City), and seasonal island routes (Nantucket to Boston, Martha's Vineyard to Boston in summer). These routes regularly price at 40 to 80 cents per mile, compared to a national average of roughly 15 to 18 cents per mile on competitive routes.

What happens to fares when a low-cost carrier leaves a route?

Fares increase, typically within months of the low-cost carrier's exit. This has been documented repeatedly, including in markets where Spirit Airlines exited following its 2024 bankruptcy network contraction. Research on the Spirit Effect found average fare reductions of 10 to 20 percent in markets Spirit entered; the reverse occurs when Spirit or similar carriers exit. The legacy carrier or remaining carrier restores fares to pre-competition levels once the competitive pressure is removed.