UPDATE: This fare sale expired at midnight Weds Sept 27. Roundtrip intra-California fares are now in the $100 range. Not bad, but not $57! As competition continues in the battle for the Golden State, we expect more fare sales like this during slower fall and winter months so stay tuned to TravelSkills.

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There’s a good old fashioned fare war happening in the California Corridor this week with roundtrip fares on several airlines as low as $51 on most NorCal-SoCal routes.

It appears that the war got started when Southwest Airlines deeply discounted round trips between its big Oakland hub and southern California cities. Spirit jumped in, too with its low fares and high fees.

Then it moved across the Bay to San Francisco and San Jose, where United and Alaska Air jumped into the fray in the battle for the Golden State.

How low are we talking? Here are some examples- but there are so many that you need to check yourself. I’ve posted roundtrip fares, but the sale applies to one-way fares, too.

Note that these roundtrip fares are available on the morning of Sept 27 and subject to change:

SFO-Burbank on United: $55 roundtrip

SFO-LAX on United: $57

San Jose-LAX/Burbank on Alaska Air: $57

LAX-Orange County on United: $57

SFO-San Diego on United: $57

Oakland-LAX on Spirit: $57

Oakland-Long Beach on JetBlue $57

SFO-Burbank, LAX, Orange County, San Diego on Southwest: $57

Oakland/San Jose-Burbank, Los Angeles, Orange County, Ontario, San Diego on Southwest: $57

Sacramento-Los Angeles, San Diego, Ontario, Burbank on Southwest or United $57

It appears that the $57 roundtrips are only available on Tuesdays, Wednesdays and Saturdays. Fares apply to flights now through mid-February. The are not available for peak holiday season flights. We found these fares on Southwest.com and Google Flights.

Note that the lowest United fares could be low-frills basic economy– awful, but acceptable for such short flights.

When roundtrip fares between SFO and LAX go below $100 round trip, it’s time to pay attention. But just $57 round trip? Wow. $57 is less that what many of us pay for a ride to or from the airport in Lyft, Uber or taxicab.

Will you take advantage of this sale? What’s the lowest fare you’ve ever seen in the California Corridor? Leave your comments below.