Chicago (ORD) to San Francisco (SFO): 1,842 miles (2,964 km) great-circle, about 4h 10m nonstop by our estimate. Cheapest fare observed: $268 round-trip on Frontier, with 1 stop, departing June 14, 2026.
$268 round-trip, Frontier F92145, departing 2026-06-14 at 07:12, returning 2026-06-20. The recorded itinerary left on a Sunday, returning on a Saturday 6 nights later; the fare was observed 50 days before departure. "Book this flight" opens Kiwi.com with the same airline and dates.
At $268, it ranked 19th of the 30 round-trip fares we recorded from ORD (median $221). That is 14.6 cents per great-circle mile (round-trip price over one-way distance), below the ORD median of 16.6 cents across 30 round-trip routes.
Routes from ORD of similar length: Guatemala City (1,899 mi) at $242 and Los Angeles (1,741 mi) at $167.
Frontier had the cheapest fare on 9 of 30 ORD routes. It is the 14th longest of the 30 routes we track from ORD.
Of 19 departure airports with a fare to San Francisco, Chicago (ORD) ranked 11th at $268. Lowest: $126 from Los Angeles (LAX); highest: $483 from New York (JFK); 6 nonstop. Cheapest-fare airlines (routes): Frontier (13), Southwest (3), American Airlines (1), United Airlines (1) and WestJet (1).
The reverse, San Francisco (SFO) to Chicago (CHI), was $364 round-trip on Alaska Airlines, 1 stop, departing April 25, 2026. San Francisco to Chicago flights.
Travelpayouts fares (cheapest per route, observed April 25, 2026); OurAirports coordinates and elevations; IANA zones America/Chicago, America/Los_Angeles; flight time is our estimate.