For the shortest trip, driving is slightly more economical than flying. But for the longer cross-country trip, flying is far cheaper. And keep in mind that this only considers solo drivers. Families or friends traveling in one vehicle can save money by driving, even on longer routes.

Flying can absolutely be cheaper than driving, particularly for solo travelers or pairs on long-distance routes where "budget" airlines are available. When calculating the cost of driving, many people only consider gas, but a true comparison must include vehicle wear and tear (depreciation), oil changes, tolls, and parking fees. For a 1,000-mile trip, the IRS mileage rate (which accounts for all these factors) often exceeds $600. In contrast, a round-trip "Basic Economy" flight on a carrier like Spirit, Frontier, or Ryanair might cost under $100 if booked in advance and traveling with only a personal item. Additionally, "opportunity cost" is a major factor; a two-hour flight replaces a 15-hour drive, saving you the cost of meals on the road and a potential hotel stay. However, the math flips when traveling with a family of four or more, as the cost of four plane tickets usually exceeds the marginal cost of adding passengers to a car. Ultimately, for long, transcontinental distances or solo "quick trips," the efficiency and competitive pricing of modern aviation often win out over the hidden costs of the road.