Substituted service under California Code of Civil Procedure §415.20 is one of the most-used and most-misunderstood provisions in the civil procedure code. Use it correctly and your case moves forward. Use it on the first attempt or without diligence and the service is voidable, the defendant defaults, and the default later gets set aside on motion.
Here is the rule.
What §415.20 actually says
CCP §415.20(b) authorizes substituted service of a summons "in lieu of personal delivery" when the summons "cannot with reasonable diligence be personally delivered." The server may leave the summons "in the presence of" one of three categories of persons at the defendant's dwelling, usual place of abode, usual place of business, or usual mailing address (other than a USPS PO box):
1. A competent member of the household at least 18 years old 2. A person apparently in charge of an office, place of business, or place of mailing 3. An adult member of the household where the defendant resides
The server then mails a copy of the summons and complaint by first-class mail to the same address. Service is deemed complete 10 days after the mailing.
The diligence requirement
The phrase that trips up paralegals is "reasonable diligence." There is no statutory minimum number of attempts, but California courts uniformly hold that at least three attempts at distinct times of day and (where practical) on distinct dates are required before sub-service is appropriate. Best practice is four attempts: a weekday morning, a weekday evening, a weekend daytime, and one more variable.
Diligence has to be documented. The affidavit needs to list each attempt by date, time, and result — "no answer," "lights on, no response," "vehicle present, no answer." Modern process servers (Servd included) GPS-stamp and photograph each attempt to support the diligence record.
Where sub-service does NOT work
Several scenarios where §415.20 is unavailable:
- Restraining orders and many protective orders — CCP §415.95 governs service of certain protective orders and generally requires personal service
- Service on minors or incapacitated persons — CCP §416.60 requires specific service on a parent, guardian, or conservator
- Service on corporations — §416.10 governs and the substituted-service rule looks different
- Out-of-state defendants — §415.40 governs service outside California with its own requirements
- Unlawful detainer cases — these have a SEPARATE sub-service rule under §415.46 that is more permissive but also more procedurally demanding (mailing requirement is different)
- Documents that are not a summons — sub-service is for the summons and complaint; for most motions, ordinary service by mail under §1013 applies
The dwelling vs. office question
The §415.20 list includes both the dwelling and the workplace. Both are valid. In practice:
- Sub-service at the workplace requires leaving with a "person apparently in charge" — a receptionist, a manager. Random coworkers don't qualify.
- Sub-service at the dwelling requires a "competent member of the household" 18 or older. A roommate counts. A live-in nanny generally counts. A house cleaner who visits twice a week does not.
- The defendant's parents at a different address than the defendant's dwelling do NOT qualify unless the parent's home is also the defendant's usual place of abode.
The mailing step
This is the part most likely to get missed. After leaving the papers, the server must mail a copy of the summons and complaint to the same address by first-class mail with prepaid postage. The affidavit of mailing is separate from the affidavit of service. Service is deemed complete 10 days after the mailing date. The 30-day answer clock starts then.
What the affidavit needs
A §415.20 affidavit needs to:
1. Identify the named defendant 2. List each attempt at personal service with date, time, place, and result 3. Identify the person who received the substituted service by name, age estimate, and apparent relationship to the defendant 4. State the date and place of the substituted service 5. Attach (or include) the proof of mailing under §415.20(b) 6. Be signed under penalty of perjury per CCP §2015.5 with the server's name and registration number
When in doubt, default to personal
Personal service is rarely wrong. Sub-service is sometimes wrong. If you can get personal service, get personal service. Sub-service is the workaround for when the defendant is unavailable, not the convenient default.