Chicago (MDW) to Philadelphia (PHL): 667 miles (1,073 km) great-circle, about 1h 50m nonstop by our estimate. Cheapest fare observed: $141 round-trip on Frontier, with 1 stop, departing May 1, 2026.
$141 round-trip, Frontier F91887, departing 2026-05-01 at 15:29, returning 2026-05-03. The recorded itinerary left on a Friday, returning on a Sunday 2 nights later; the fare was observed 6 days before departure. "Book this flight" opens Kiwi.com with the same airline and dates.
At $141, it ranked 3rd of the 30 round-trip fares we recorded from MDW (median $316). That is 21.1 cents per great-circle mile (round-trip price over one-way distance), close to the MDW median of 22.1 cents across 30 round-trip routes.
Routes from MDW of similar length: New York (730 mi) at $211 and Atlanta (592 mi) at $105.
Frontier had the cheapest fare on 11 of 30 MDW routes. It is the 28th longest of the 30 routes we track from MDW.
Of 13 departure airports with a fare to Philadelphia, Chicago (MDW) ranked 6th at $141. Lowest: $69 from Tampa (TPA); highest: $413 from Punta Cana (PUJ); 5 nonstop. Cheapest-fare airlines (routes): Frontier (10), Southwest (1), Spirit (1) and Sun Country (1).
The reverse, Philadelphia (PHL) to Chicago (CHI), was $167 round-trip on Frontier, 1 stop, departing June 3, 2026. Philadelphia to Chicago flights.
Travelpayouts fares (cheapest per route, observed April 25, 2026); OurAirports coordinates and elevations; IANA zones America/Chicago, America/New_York; flight time is our estimate.