Delta Airlines offers select roundtrip fares in the U.S. with prices starting at $144.20. (Click on "Delta Airlines" in the top line to see this sale; all taxes are included.) That's the lowest base rate we could find for select routes by $9. This price is valid on flights departing from Los Angeles, CA, (LAX) with arrival in San Francisco, CA, (SFO) on April 14 and return on April 20. Book this travel deal by April 6 for travel through June 6. Click here to see more routes.