- The BTS average domestic itinerary fare was $387.01 in 2025, and $427.81 in the first quarter of 2026. BTS itinerary fares are round-trip fares unless the customer bought no return trip.
- On fuel alone, one 2025 average fare buys the fuel for about 3,647 round-trip miles in the average midsize car (EPA class) at the 2025 average regular gasoline price of $3.10, and about 2,455 miles in the average standard SUV (EPA class).
- Fuel is a cost per vehicle and airfare is a cost per person. Against four tickets, the same fuel-only break-even distances are four times longer: about 14,589 miles for the midsize car.
- The IRS business mileage rate (72.5 cents per mile in 2026) includes fixed costs such as insurance and depreciation. Used as the cost of a trip, it puts the solo break-even at about 534 miles; the IRS variable-cost-only rate (20.5 cents) puts it at about 1,888 miles. The right basis depends on how much of a trip's cost is fixed.
01 The Inputs
Every input is a national average, not a route or a vehicle. The comparison shows where driving and flying cross under stated assumptions; it does not price a particular trip.
| Input | Value | Source |
|---|---|---|
| Average domestic airfare, 2025 | $387.01 | BTS annual average itinerary fare, current dollars |
| Average domestic airfare, first quarter 2026 | $427.81 | BTS quarterly series |
| Regular gasoline, 2025 annual mean | $3.10 per gallon | EIA weekly U.S. regular price, averaged over 2025 |
| Regular gasoline, latest week (2026-10-12) | $4.33 per gallon | EIA weekly U.S. regular price |
| Midsize car / standard SUV / standard pickup fuel economy | 29.2 / 19.6 / 18.3 MPG | EPA combined MPG, unweighted mean of all non-electric model year 2024 and 2025 vehicles in each EPA class (hybrids and diesels included) |
| IRS business standard mileage rate, 2026 | 72.5 cents per mile | CRS IN12320, Table 1 |
| IRS medical and moving rate, 2026 | 20.5 cents per mile | CRS IN12320, Table 1 |
BTS describes its fares this way: "Itinerary fares consist of round-trip fares, unless the customer does not purchase a return trip. In that case, the one-way fare is included." The fare is one national average across all routes and distances, so it does not vary with how far the trip goes.
BTS, Annual U.S. Domestic Average Itinerary Fare in Current and Constant Dollars, table note.02 Fuel-Only Driving Cost
Fuel cost for a round trip is the distance divided by miles per gallon, times the price of a gallon. The table applies the 2025 average price of $3.10 to the three vehicle classes. The last two columns apply the IRS rates for comparison.
| Round-trip distance | Midsize car fuel | Standard SUV fuel | Standard pickup fuel | IRS variable-cost rate | IRS business rate |
|---|---|---|---|---|---|
| 500 miles | $53 | $79 | $85 | $102 | $362 |
| 1,000 miles | $106 | $158 | $170 | $205 | $725 |
| 2,000 miles | $212 | $315 | $339 | $410 | $1,450 |
| 3,000 miles | $318 | $473 | $509 | $615 | $2,175 |
| 4,000 miles | $424 | $631 | $679 | $820 | $2,900 |
At the latest weekly price of $4.33, fuel costs about 40% more, and the fuel-only break-even for the midsize car falls from about 3,647 to about 2,608 round-trip miles.
Calculated: $387.01 ÷ ($4.33 ÷ 29.2 MPG).Estimate your vehicle's total driving cost using official EPA fuel economy data.
Use the Calculator03 Break-Even Distances
The break-even distance is the round-trip distance at which the cost of driving equals the airfare: $387.01 for one traveler, or $1,548.04 for four travelers, since the car carries all four for the same fuel. Below the break-even distance driving costs less on that basis; above it, flying does.
| Cost basis for driving | Solo traveler | Four travelers |
|---|---|---|
| Fuel only, midsize car (29.2 MPG) | 3,647 miles | 14,589 miles |
| Fuel only, standard SUV (19.6 MPG) | 2,455 miles | 9,819 miles |
| Fuel only, standard pickup (18.3 MPG) | 2,281 miles | 9,125 miles |
| IRS variable-cost rate (20.5 cents per mile) | 1,888 miles | 7,551 miles |
| IRS business rate, all fixed and variable costs (72.5 cents per mile) | 534 miles | 2,135 miles |
The IRS rates bracket the answer. The business rate includes all fixed and variable costs of operating a vehicle. According to the Congressional Research Service, fixed costs "do not vary based on the distance the vehicle travels, including insurance and depreciation of the vehicle's value," while variable costs include fuel, tires, brakes and other components, and the medical and moving rate includes only variable costs. Fixed costs are incurred whether or not a given trip is made, so the business rate overstates what one trip adds to a household's costs. Fuel alone understates it, since tires, brakes and other components also wear with distance. The variable-cost rate, which covers fuel and those components, is the closer reference for the cost of one trip.
Congressional Research Service, IN12320 (Feb. 17, 2026), "How Are the Standard Mileage Rates Set?" None of the IRS standard mileage rates include tolls or parking, per the same source.Fares also change over time. The first-quarter 2026 fare of $427.81 is 10.5% above the 2025 average, and every break-even distance above scales up by the same proportion if the higher fare is used. See domestic airfare prices by year for the full history.
04 What Is Not Included
The comparison leaves out costs and factors that can matter as much as fuel and airfare. This site has no federal source in its data files for their national averages, so it does not put dollar figures on them.
- Route-specific fares. The BTS fare is one national average across all routes and distances. A given route can cost much less or much more.
- Driving: lodging and meals on multi-day trips, tolls and parking, and wear beyond fuel.
- Flying: getting to and from airports, ground transportation at the destination, baggage fees and parking.
- Time. Driving takes far longer than flying over long distances, and the value of that time differs by traveler.
- Passengers and cargo. More people or luggage change the fuel economy slightly and the ticket cost a lot.
05 Data Sources
- Bureau of Transportation Statistics. Annual U.S. Domestic Average Itinerary Fare in Current and Constant Dollars (1995 to 2026) and the quarterly national domestic average fare series through the first quarter of 2026. bts.gov
- U.S. Energy Information Administration. Weekly Retail Gasoline and Diesel Prices, U.S. regular. eia.gov
- U.S. Environmental Protection Agency and Department of Energy. Fuel economy dataset for model years 2024 and 2025 (FuelEconomy.gov). fueleconomy.gov
- Congressional Research Service. IN12320, IRS Standard Mileage Rates (Feb. 17, 2026).