The rules for service of process in California require you to deliver a copy of the summons and complaint to the defendant through one of the methods set out in the Code of Civil Procedure, have a qualified adult make that delivery, and then file a proof of service with the court. Until that happens correctly, the case cannot move forward — the court has no authority to enter orders against a person who was never properly served.
Who Can Serve the Papers
The person who delivers the documents must be at least 18 years old and cannot be a party to the lawsuit.1California Legislative Information. California Code of Civil Procedure 414.10 If you filed the complaint, you cannot hand the papers to the defendant yourself. Most plaintiffs hire a registered process server or use the county sheriff’s office. You can also ask a friend, coworker, or any other adult with no stake in the case, but that person will have to complete and sign a proof of service afterward, so choose someone who will handle the paperwork accurately.
What You Need to Deliver
At a minimum, the server delivers a copy of the summons and the complaint. The summons is the court-issued document telling the defendant they have 30 days to file a written response and warning that failure to respond can lead to a default judgment, including wage garnishment or seizure of property.2California Legislative Information. California Code of Civil Procedure CCP 412.20 The complaint lays out the facts and the relief you are seeking.
You also need the right proof of service form on hand before the delivery attempt. For a summons, that is Judicial Council form POS-010.3California Courts Self-Help Guide. Proof of Service of Summons For other civil papers that are not a summons, use form POS-040.4California Courts. Proof of Service – Civil (POS-040) Both ask for the exact date, time, and address of delivery.
Personal Service
Personal service is the cleanest method: the server physically hands the summons and complaint to the defendant. Service is complete the moment the papers are delivered.5California Legislative Information. California Code of Civil Procedure CCP 415.10 The server should note the delivery date on the face of the summons copy at the time of delivery, though failing to do so does not invalidate the service.
If the defendant refuses to take the papers, the server does not have to force them into the person’s hands. California courts have held that leaving the documents at the person’s feet or in their immediate vicinity, after identifying what they are, counts as valid personal delivery. Refusing to accept papers is not a way to dodge service.
Substituted Service
When the server cannot reach the defendant in person despite reasonable diligence, substituted service is the next option. Reasonable diligence generally means multiple attempts at different times and on different days, each one documented.
Once those attempts fail, the server can leave the papers with a competent household member who is at least 18 years old, or with a person apparently in charge at the defendant’s workplace or usual mailing address, and must tell that person what the documents are about. The server then mails a second copy of the summons and complaint by first-class mail to the same address. Service is not complete when the papers are dropped off. It is deemed complete on the 10th day after the mailing.6California Legislative Information. California Code of Civil Procedure CCP 415.20 That date drives the defendant’s response deadline.
Service by Mail With Acknowledgment
When the parties cooperate, service can happen entirely by mail. The plaintiff sends the summons and complaint by first-class mail along with two copies of a notice and acknowledgment form and a prepaid return envelope. Service is complete only when the defendant signs the acknowledgment and it is returned to the sender.7California Legislative Information. California Code of Civil Procedure CCP 415.30
The catch is cooperation. If the form is not signed and returned within 20 days, the plaintiff has to switch to another method. A defendant who ignored the acknowledgment can then be held liable for the reasonable costs of that second round of service, which usually means paying for a professional process server. Courts award these costs routinely.7California Legislative Information. California Code of Civil Procedure CCP 415.30
Serving Someone Outside California
You can serve an out-of-state defendant using any of the methods above, or by sending the summons and complaint by first-class mail with a return receipt requested. When you use that mail method for an out-of-state defendant, service is deemed complete on the 10th day after mailing. It does not depend on the defendant returning a signed form.
Foreign-country service is different. If the country is a party to the Hague Service Convention, you generally must follow that treaty’s procedures, which route documents through a designated central authority abroad. Some member countries have objected to service by mail, making that route unavailable there. International service is slow and procedurally demanding enough that consulting an attorney before attempting it is worth the cost.
Service by Publication
If you genuinely cannot locate the defendant after reasonable diligence, you can ask the court for permission to serve by publishing the summons in a newspaper. This is a last resort. The court will grant the order only if you file an affidavit showing you tried the other methods and could not reach the defendant, and that either a valid cause of action exists against the person or the case involves property in California.8California Legislative Information. California Code of Civil Procedure 415.50
If granted, the court names a specific newspaper most likely to reach the defendant and orders publication for the period required by Government Code Section 6064, which generally means once a week for four successive weeks. If you learn the defendant’s address before publication ends, you must also mail a copy of the summons, complaint, and court order to that address. Judges routinely deny publication requests when the affidavit shows halfhearted search efforts.8California Legislative Information. California Code of Civil Procedure 415.50
Serving a Corporation or LLC
Serving a business is different from serving a person. You can deliver the summons and complaint to the company’s designated agent for service of process, or to one of these officers: the president, CEO, vice president, secretary, assistant secretary, treasurer, assistant treasurer, controller, chief financial officer, or general manager. Anyone the corporation has authorized to accept service also qualifies. For banks, a cashier or assistant cashier can accept papers.9California Legislative Information. California Code of Civil Procedure CCP 416.10
LLCs and other California-registered business entities are required to designate a registered agent for service of process. If that agent’s information is outdated or the entity never appointed one, the court may allow alternative service methods, and a default can be entered before the company even realizes it was sued.
The Deadlines That Matter
Three deadlines control the timing of service.
First, California Rule of Court 3.110 requires the complaint to be served within 60 days of filing unless the court grants an extension. Courts track this. If you fall behind without good cause, the court can issue an order to show cause why the case should not be dismissed.10California Courts. Rule 3.110 – Time for Service of Complaint
Second, the outer limit is three years from the date the complaint is filed. If service is not completed within that window, the court must dismiss. The proof of service must be filed within 60 days after that three-year deadline passes.11California Legislative Information. California Code of Civil Procedure 583.210 Waiting is risky in any event: witnesses move, memories fade, evidence disappears.
Third, once properly served, the defendant has 30 days to file a written response.2California Legislative Information. California Code of Civil Procedure CCP 412.20 The parties can agree to a single 15-day extension without court approval; anything beyond that requires a court order.10California Courts. Rule 3.110 – Time for Service of Complaint If the defendant does not respond in time, the plaintiff can ask the clerk to enter a default, which sets up a default judgment for the relief the complaint requested.
Filing the Proof of Service
After successful delivery, the server completes and signs the proof of service under penalty of perjury. The form must show the time, place, and method of service, along with the name and capacity of the person who received the documents. For service by mail with acknowledgment, the proof must include the signed acknowledgment form. For service by publication, the proof requires an affidavit from the newspaper’s publisher confirming the publication dates.12California Legislative Information. California Code of Civil Procedure CCP 417.10
The completed proof gets filed with the court clerk. Many California courts accept electronic filing; you can also file in person or by mail. Until the proof of service is on file, the court will not schedule hearings, enter a default, or take any further action in the case.13California Courts. Request a Default
When Service Was Defective
A defendant who believes the papers were not properly served can file a motion to quash service of summons. That motion must be filed before any other response, such as an answer or demurrer. Filing any other responsive pleading first waives the right to challenge service.14California Legislative Information. California Code of Civil Procedure CCP 418.10
Common grounds include delivering papers to the wrong person, skipping the required mailing after substituted service, or never attempting personal delivery before resorting to an alternative method. A successful motion to quash usually does not dismiss the case; the plaintiff simply gets another chance to serve the defendant correctly.
If a default judgment has already been entered because of defective service, the defendant can ask the court to set it aside. Under CCP Section 473(d), courts can vacate any void judgment, and a judgment entered without proper service is void because the court never had personal jurisdiction over the defendant.15California Legislative Information. California Code of Civil Procedure CCP 473 Unlike motions based on excusable neglect, which have a six-month deadline, a motion to vacate a void judgment for lack of proper service has no fixed time limit. The defendant still has to prove at a hearing that service was actually defective, so gather evidence early.