Fares are per person; gas is per car
The table compares the average round-trip fare with the gas for an example drive of 600 miles each way (1,200 miles) in a 30-MPG car. The gas total stays at $179.12 however many people ride; the fares grow with each traveler.
| Travelers | Round-trip fares, all travelers | Gas for the car | Gas per person |
|---|---|---|---|
| 1 | $549 | $179.12 | $179.12 |
| 2 | $1,098 | $179.12 | $89.56 |
| 3 | $1,647 | $179.12 | $59.71 |
| 4 | $2,196 | $179.12 | $44.78 |
| 5 | $2,745 | $179.12 | $35.82 |
Fares are a national average across all domestic routes, not the fare for your route or dates. Gas uses EIA’s U.S. average and the trip gas cost engine.
Neither column is a full trip cost; the sections below list what each leaves out.
Reference: BTS: Second Quarter 2026 Average Air Fare Increased 2.0% from First Quarter 2026 · EIA: Gasoline and Diesel Fuel Update
How far could you drive for the price of the tickets?
Divide the fares by the car’s gas cost per mile. At 30 MPG and $4.478 a gallon, gas costs $0.14927 a mile ($4.478 ÷ 30).
For one traveler, gas matches the average fare at about 1,840 miles each way. For two, it takes about 3,680 miles each way, which is longer than driving I-80 from end to end (2,891.59 miles by FHWA’s count), so for two or more travelers, the gas for a drive as long as I-80 end to end still costs less than their average fares.
| Travelers | Round-trip fares | Miles of gas, round trip | Each way |
|---|---|---|---|
| 1 | $549 | 3,678 | 1,839 |
| 2 | $1,098 | 7,356 | 3,678 |
A derived comparison: fares ÷ gas cost per mile, from unrounded values. It counts gas only, so it overstates how far driving stays cheaper once lodging, meals and wear are added.
A car that gets fewer miles per gallon, or higher gas prices, shortens these distances in proportion.
Reference: BTS: Second Quarter 2026 Average Air Fare Increased 2.0% from First Quarter 2026 · EIA: Gasoline and Diesel Fuel Update · FHWA: Route Log and Finder List, Table 1 (Main Routes)
What the average fare leaves out
BTS counts the ticket price including taxes and required fees. It does not include fees for optional services, such as baggage fees, seat upgrades and choosing an assigned seat. For one-way tickets, the second quarter of 2026 average was $312.
Flying also brings costs that aren’t on the ticket: getting to and from the airport, parking there, and a rental car or rides at your destination if you need them.
Reference: BTS: Second Quarter 2026 Average Air Fare Increased 2.0% from First Quarter 2026
What the gas figure leaves out
Driving adds tolls, parking at the destination, and lodging and meals on a trip long enough to need them. The miles also add wear and depreciation to the car, which you don’t pay at the pump.
Then there’s time. At an average of 60 mph, used here only as an example, the 1,200-mile round trip is 20 hours behind the wheel, before stops. Whether that time is a cost or part of the trip is your call.
A quick way to decide
Compare the two trips on the same basis:
Price the gas for your drive ↗
- Price the actual fares for your dates and add bag and seat fees for everyone flying.
- Enter your route’s miles and your car’s MPG in the trip calculator, with the gas price for your region.
- Add tolls and parking to the drive, and airport parking or rides to the flight.
- Add lodging and meals for any overnight stops on the drive.
- Look at the difference per person, then weigh the hours each option takes.
Use the calculator with your numbers
The worked example below is the 1,200-mile round trip for four people, from the trip gas cost calculator’s engine.
| Item | Example result |
|---|---|
| Gallons | 40 gallons |
| Gas for the car | $179.12 |
| Gas per person, 4 travelers | $44.78 |
| Gas cost per mile | $0.149 |
Authored example drive. Compare the per-person gas with the fares for your route, and add the costs each option leaves out.
Illustrative figures, not market averages. The underlying costs are calculated with the same engine as the tool; additional derived measures are labeled.
Price the gas for my drive ↗About this guide
Prepared by RealCostTools with AI-assisted research and drafting. Sources and calculations were checked October 4, 2026. Fares are BTS national averages for the second quarter of 2026; gas uses EIA’s U.S. average for the week of September 21, 2026. The drive is an example, not a typical trip.
Sources and calculation notes
- BTS: Second Quarter 2026 Average Air Fare Increased 2.0% from First Quarter 2026
BTS 26-73, dated September 29, 2026, which revised the September 25 release after carriers re-submitted data; checked October 4, 2026. Average domestic itinerary fare $445 in the second quarter of 2026; round trips $549, one-way trips $312. Includes taxes and fees required to board; excludes optional fees such as bags and seats. Next release on or around January 8, 2027.
- EIA: Gasoline and Diesel Fuel Update
U.S. regular gasoline, $4.478 a gallon for the week of September 21, 2026, released September 22, 2026; all taxes included. Checked October 4, 2026; the trip calculator opens on EIA’s newest week.
- FHWA: Route Log and Finder List, Table 1 (Main Routes)
I-80 is 2,891.59 miles end to end (routes as of December 31, 2025; page updated March 10, 2026). Checked October 4, 2026. Used only to put the break-even distance in context.
- RealCostTools: trip gas cost methodology
The formulas behind the gas amounts in this guide.
Read the trip gas cost methodology for the model assumptions and excluded costs.
Published . Sources checked . Editorial policy · Corrections