Cal. Civ. Code § 704.19

704.19 Notice necessary to terminate periodic tenancies and tenancies at will.
(1) Scope of section. The following types of tenancies, however created, are subject to this section:
(a) A periodic tenancy, whether a tenancy from year-to-year, from month-to-month, or for any other periodic basis according to which rent is regularly payable; and
(b) A tenancy at will.
(2) Requirement of notice.
(a) A periodic tenancy or a tenancy at will can be terminated by either the landlord or the tenant only by giving to the other party written notice complying with this section, unless any of the following conditions is met:
1. The parties have agreed expressly upon another method of termination and the parties’ agreement is established by clear and convincing proof.
2. Termination has been effected by a surrender of the premises.
3. Subsection (6) applies.
(b)
1. A periodic tenancy can be terminated by notice under this section only at the end of a rental period. In the case of a tenancy from year-to-year the end of the rental period is the end of the rental year even though rent is payable on a more frequent basis.
2. Notwithstanding subd. 1., nothing in this section prevents termination of a tenancy before the end of a rental period because of an imminent threat of serious physical harm, as provided in s. 704.16, or for criminal activity or drug-related criminal activity, nonpayment of rent, or breach of any other condition of the tenancy, as provided in s. 704.17.
(3) Length of notice. At least 28 days’ notice must be given except in the following cases: If rent is payable on a basis less than monthly, notice at least equal to the rent-paying period is sufficient; all agricultural tenancies from year-to-year require at least 90 days’ notice.
(4) Contents of notice. Notice must be in writing, formal or informal, and substantially inform the other party to the landlord-tenant relation of the intent to terminate the tenancy and the date of termination. A notice is not invalid because of errors in the notice which do not mislead, including omission of the name of one of several landlords or tenants.
(5) Effect of inaccurate termination date in notice. If a notice provides that a periodic tenancy is to terminate on the first day of a succeeding rental period rather than the last day of a rental period, and the notice was given in sufficient time to terminate the tenancy at the end of the rental period, the notice is valid; if the notice was given by the tenant, the landlord may require the tenant to remove on the last day of the rental period, but if the notice was given by the landlord the tenant may remove on the last day specified in the notice. If a notice specified any other inaccurate termination date, because it does not allow the length of time required under sub. (3) or because it does not correspond to the end of a rental period in the case of a periodic tenancy, the notice is valid but not effective until the first date which could have been properly specified in such notice subsequent to the date specified in the notice, but the party to whom the notice is given may elect to treat the date specified in the notice as the legally effective date. If a notice by a tenant fails to specify any termination date, the notice is valid but not effective until the first date which could have been properly specified in such notice as of the date the notice is given.
(6) Tenant moving out without notice. If any periodic tenant vacates the premises without notice to the landlord and fails to pay rent when due for any period, such tenancy is terminated as of the first date on which it would have terminated had the landlord been given proper notice on the day the landlord learns of the removal.
(7) When notice given. Notice is given on the day specified below, which is counted as the first day of the notice period:
(a) The day of giving or leaving under s. 704.21 (1) (a) and (2) (a) and (b).
(b) The day of leaving or affixing a copy or the date of mailing, whichever is later, under s. 704.21 (1) (b) and (c).
(c) The 2nd day after the day of mailing if the mail is addressed to a point within the state, and the 5th day after the day of mailing in all other cases, under s. 704.21 (1) (d) and (2) (c).
(d) The day of service under s. 704.21 (1) (e) and (2) (d).
(e) The day of actual receipt by the other party under s. 704.21 (5).
(8) Effect of notice. If a notice is given as required by this section, the tenant is not entitled to possession or occupancy of the premises after the date of termination as specified in the notice.