Legal Question in Landlord & Tenant Law in California

Legally, no. But, perhaps the owner can work with you to get another tenant quickly to lessen (mitigate) the amount of money you'd have to pay, if any. Give the owner a call and be frank about your needs without being argumentative. Perhaps you could offer to pay for the ad for a new tenant just to get out of the lease. Be creative, and good luck!

I was in a similar situation many years ago, and the landlord just agreed to let me out in exchange for 1/2 my deposit to cover his re-renting expense. If the landlord won't cooperate, however, you may be in for some significant expense. Once you notify the landlord you will not move in, he is under an obligation to take all commercially reasonable steps to re-rent the property, but as long as he does so, you are on the hook for the rent from 8/1 until a new tenant moves in.