Only in tenancies on a month-to-month basis or less, and situations where the lease will be expiring in thirty days, may a landlord exercise the right to raise the rent or make other legal, non-discriminatory and non-retaliatory changes to the terms of the tenancy. To legally change the terms of the tenancy the landlord must give written advance notice to the tenant of the intended changes at least as long as the term of the tenancy. For instance, on a month-to-month tenancy, the landlord must provide the notice at least thirty days before the intended date of the change of terms. A new law that went into effect on January 1, 2001, states that if a landlord wishes to raise the rent to an amount greater than 10% of the then existing monthly rental rate, the landlord must give at least sixty days notice of rent increase. This sixty day notice of rent increase to an amount greater than 10% may now be served by first class mailing rather than in the previously limited way of either personal service, substituted service or by posting and mailing. If a mailing is the method chosen for notifying the tenant of the intent to increase rent, the landlord must add an additional five days to the sixty days before the rent increase will go into effect. You should also note that if in the last twelve months (prior to the effective date of the increase) the landlord has raised the rent at all, if the combined amount of the rent increase is greater than 10%, then the sixty day plus five day requirement applies. If the landlord wishes to raise the rent to an amount that is 10% or less, the notice must also be in writing; this notice may be served by either personal delivery upon the tenant or by first class mailing. If the method of notice is by mailing, an additional five days must be added to the thirty day period for the notice to be effective.

Subject to the sixty plus five day period that is discussed above for situations where the landlord intends to raise the rent to an amount greater than 10% of the then existing rent, or the thirty plus five day period where the landlord intends to raise the rent to an amount of 10% or less, many landlords have the mistaken belief that the "non-rent increase" Notice of Change of Terms of Tenancy may be merely mailed to the tenant; however, to be legally enforceable, the written notice must be served upon the tenant in the same manner as a Three Day Notice to Pay Rent or Quit; namely, by personal delivery; substituted service (handing a copy of the Notice of Change of Terms of Tenancy to someone of suitable age and discretion at the tenancy address or the tenant?s business address, and thereafter mailing a copy by first class mail to the tenancy address); or by posting a copy of the notice in a conspicuous place at the tenancy premises - usually the front door - and thereafter mailing a copy by first class mail to the tenancy address.

See the Code Section: Civil Code Section 827: (a) Except as provided in subdivision (b), in all leases of lands or tenements, or of any interest therein, from week to week, month to month, or other period less than a month, the landlord may, upon giving notice in writing to the tenant, in the manner prescribed by Section 1162 of the Code of Civil Procedure, change the terms of the lease to take effect, as to tenancies for less than one month, upon the expiration of a period at least as long as the term of the hiring itself, and, as to tenancies from month to month, to take effect at the expiration of not less than 30 days, but if that change takes effect within a rental term, the rent accruing from the first day of the term to the date of that change shall be computed at the rental rate obtained immediately prior to that change; provided, however, that it shall be competent for the parties to provide by an agreement in writing that a notice changing the terms thereof may be given at any time not less than seven days before the expiration of a term, to be effective upon the expiration of the term. The notice, when served upon the tenant, shall in and of itself operate and be effectual to create and establish, as a part of the lease, the terms, rents, and conditions specified in the notice, if the tenant shall continue to hold the premises after the notice takes effect. (b) (1) In all leases of a residential dwelling, or of any interest therein, from week to week, month to month, or other period less than a month, the landlord may increase the rent provided in the lease or rental agreement, upon giving written notice to the tenant, as follows, by either of the following procedures: (A) By delivering a copy to the tenant personally. (B) By serving a copy by mail under the procedures prescribed in Section 1013 of the Code of Civil Procedure. (2) If the proposed rent increase for that tenant is 10 percent or less of the rental amount charged to that tenant at any time during the 12 months prior to the effective date of the increase, either in and of itself or when combined with any other rent increases for the 12 months prior to the effective date of the increase, the notice shall be delivered at least 30 days prior to the effective date of the increase, and subject to Section 1013 of the Code of Civil Procedure if served by mail. (3) For an increase in rent greater than the amount described in paragraph (2), the minimum notice period required pursuant to that paragraph shall be increased by an additional 30 days, and subject to Section 1013 of the Code of Civil Procedure if served by mail. This paragraph shall not apply to an increase in rent caused by a change in a tenant's income or family composition as determined by a recertification required by statute or regulation. (c) If a state or federal statute, state or federal regulation, recorded regulatory agreement, or contract provides for a longer period of notice regarding a rent increase than that provided in subdivision (a) or (b), the personal service or mailing of the notice shall be in accordance with the longer period. (d) This section shall be operative only until January 1, 2006, and as of that date is repealed, unless a later enacted statute, which is enacted on or before January 1, 2006, deletes or extends that date.