Generally speaking, if there is some doubt about what kind of notice is required and the tenancy is a “periodic” tenancy (for example month-to-month), the safest way to deal with that is often to simply issue a sixty-day notice to quit. However, there are several instances where a thirty-day notice is valid. For example, if a tenant has resided in a tenancy for less than one year and the rental agreement is for a month-to-month tenancy, a thirty-day notice is valid notice. However, if the tenant has resided in the tenancy for longer than a year, then California Code of Civil Procedure 1946.1 requires a sixty-day notice.
No reason need to be given to issue such a notice. That differs from other types of notices involving failure to pay rent, breach of the lease agreement, or nuisance.