Legal Question in Real Estate Law in California

If the rent is due on the 1st it is late on the 2nd. There is no law or policy in California establishing a grace period for payment of rent. "Due on the first" is given its literal meaning, except that if the first is a Saturday, Sunday or holiday, the rent may be paid on the following business day without being considered late.

However, the landlord cannot immediately file a legal action, at least not the one it is most likely to file, an unlawful detainer...a three-day notice to pay rent or quit is required.

What part of 'due on the 1st' did you not understand? Read your lease to determine the late fees you'll incur, and the default notices and dates he can follow to evict you for non-payment.

The landlord can start eviction by serving you with a three day pay or quit as soon as rent is late.