United Airlines via DealBase discounts select nationwide 1-way fares, with prices starting from $64. That's the best price we could find for select routes on comparable 3-star carriers by $9. Book this travel deal by June 6 for travel from August 20 through December 18. Buy Now Tips On the DealBase landing page, click on "United Airlines" in the top line to see this sale; we found lower fares within. We found this price on flights departing on August 21 from San Diego, CA (SAN) to San Francisco, CA (SFO). All prices, dates, and booking details were valid at the time of publication.