Service of Unlawful Detainer Notices.  With some exceptions, unlawful detainer notices must be served either: 

• by personal delivery to the person entitled to the notice; 
• if the person entitled to the notice is not on the unlawfully held premises, by leaving a copy with a person of suitable age and discretion at the premises and sending a copy by certified mail posted from within the state to the last known address of the person entitled to the notice; or 
• if the person entitled to the notice is a tenant or unlawful occupant whose place of residence is not known, or if a person of suitable age and discretion cannot be found at the premises, by doing all three of the following: affixing a copy of the notice in a conspicuous place on the premises unlawfully held, delivering a copy to a person residing at the premises if such a person can be found, and mailing a copy addressed to the tenant or unlawful occupant at the unlawfully held premises.

When a copy of an unlawful detainer notice is sent through the mail, service is deemed complete when the copy is deposited in the mail by certified mail, has postage prepaid, is posted from within the state, and is directed to the last known address of the person entitled to notice.  When service is made by mail, five additional days must be allowed before the commencement of an action based upon the notice.

Notices Required to be Served in the Same Manner as Unlawful Detainer Notices.  Certain notices are required to be served in the same manner as unlawful detainer notices, including the following:

• rent increase notices under both the Residential Landlord-Tenant Act (RLTA) and the Manufactured/Mobile Home Landlord-Tenant Act;
• many notices for termination of a tenancy under the RLTA, including notices of the expiration of a tenancy for a specified time;
• certain notices of default on rent due under a court-ordered payment plan;
• notices of a condominium conversion and public offering statement to residential tenants in a building that the owner intends to convert into a condominium; and
• a copy of the summons and complaint in cases of default on rent for real property where the rent is $40 or less.

When a copy of an unlawful detainer notice is sent through the mail, service is deemed complete when the copy is deposited in the mail from within the state, properly addressed, with postage prepaid.  The requirement for certified mail delivery is removed.  

With some exceptions, unlawful detainer notices must be served either: 

• by personal delivery to the person entitled to the notice; 
• if the person entitled to the notice is not on the unlawfully held premises, by leaving a copy with a person of suitable age and discretion at the premises and sending a copy through the mail addressed to the person entitled to the notice at the person's place of residence—instead of sending a copy by certified mail posted from within the state to the last known address of the person entitled to the notice; or 
• if the person entitled to the notice is a tenant or unlawful occupant whose place of residence is not known, or if a person of suitable age and discretion cannot be found at the premises, by doing all three of the following: affixing a copy of the notice in a conspicuous place on the premises unlawfully held, delivering a copy to a person residing at the premises if such a person can be found, and mailing a copy addressed to the tenant or unlawful occupant at the unlawfully held premises.