Roundtrip Airfares: Chicago, IL to/from San Diego, CA via Major Airlines BE $157 (Travel Oct-Dec 2025)

Roundtrip Airfares: Chicago, IL to/from San Diego, CA via Major Airlines for $159 (Travel Oct-Dec 2025). Alaska, Southwest, United and American Airlines all have round trip airfares from Chicago (ORD) to San Diego (SAN) for $159, nonstop. These are basic economy fares. On Alaska, Southwest and American you may have a personal item and a carry-on bag. On United, you may only have a personal item. There is no seat selection and no change.