Philadelphia (PHL) to San Diego (SAN): 2,365 miles (3,806 km) great-circle, about 5h 15m nonstop by our estimate. Cheapest fare observed: $196 round-trip on Frontier, with 1 stop, departing May 13, 2026.
$196 round-trip, Frontier F93339, departing 2026-05-13 at 20:35, returning 2026-05-18. The recorded itinerary left on a Wednesday, returning on a Monday 5 nights later; the fare was observed 18 days before departure. "Book this flight" opens Kiwi.com with the same airline and dates.
At $196, it ranked 11th of the 30 round-trip fares we recorded from PHL (median $234). That is 8.3 cents per great-circle mile (round-trip price over one-way distance), below the PHL median of 21.3 cents across 30 round-trip routes.
Routes from PHL of similar length: Los Angeles (2,396 mi) at $301 and Las Vegas (2,171 mi) at $122.
Frontier had the cheapest fare on 19 of 30 PHL routes. It is the 6th longest of the 30 routes we track from PHL.
Of 11 departure airports with a fare to San Diego, Philadelphia (PHL) ranked 5th at $196. Lowest: $76 from San Francisco (SFO); highest: $563 from Washington DC (IAD); 4 nonstop. Cheapest-fare airlines (routes): Frontier (8), Alaska Airlines (2) and WestJet (1).
Travelpayouts fares (cheapest per route, observed April 25, 2026); OurAirports coordinates and elevations; IANA zones America/New_York, America/Los_Angeles; flight time is our estimate.