Antioch had 115,291 residents at the 2020 Census. The Census Bureau's July 2025 estimate puts it at 118,958, which is more than its estimate for Richmond (114,861). That makes Antioch the second-largest city in Contra Costa County by the newest count, behind Concord. We serve summonses, complaints, subpoenas, restraining orders, family law papers and eviction notices anywhere in the city.
Our only office is in Sacramento, 46.8 miles from Antioch in a straight line. Requests come in online, and you can get status updates by email.
Where are Antioch cases filed?
Antioch is an East County city, and the county court splits its work by case type. The where-to-file page on contracosta.courts.ca.gov lists Antioch's ZIP Codes, 94509 and 94531, under the Richard E. Arnason Justice Center in Pittsburg for the cases filed by city. Everything else goes to Martinez.
| Antioch case | Filed at | Distance from central Antioch |
|---|---|---|
| Small claims | Arnason Justice Center, 1000 Center Dr, Pittsburg | about 5.8 miles |
| Unlawful detainer (eviction) | Arnason Justice Center, Pittsburg | about 5.8 miles |
| Civil, limited and unlimited | Wakefield Taylor Courthouse, 725 Court St, Martinez | about 18.6 miles |
| Family law, restraining orders, adoptions | Spinetta Family Law Center, 751 Pine St, Martinez | about 17.8 miles |
| Probate, guardianship, conservatorship | Wakefield Taylor Courthouse, Martinez | about 18.6 miles |
Source: Contra Costa County Superior Court where-to-file and location pages, checked October 2026. Distances are straight-line, from the Census center point of Antioch to the map points on the court's pages.
The Pittsburg building has seven courtrooms. Its page lists family law among the cases heard there, along with small claims, evictions, criminal and traffic, plus some domestic violence and juvenile matters. Filing is a separate question. The court sends family law paperwork to Spinetta in Martinez, with one narrow exception covered in the FAQs below.
What to know before a run to the Pittsburg courthouse
The court calls the Arnason Justice Center the courthouse for the former Delta Judicial District. It serves Antioch, Bay Point, Bethel Island, Brentwood, Byron, Discovery Bay, Knightsen, Oakley and Pittsburg. Its page gives these working details:
- Filing windows open at 8:00 a.m. and close at 4:00 p.m.
- Phones at (925) 608-1000 are answered from 8:00 a.m. to 3:00 p.m. After that, voicemail picks up.
- One entrance, with a security check for everyone.
- Building hours run 8:00 a.m. to 5:00 p.m., Monday through Friday.
For small claims, the court holds hearings in person. A remote appearance needs compliance with CCP § 367.75 and form RA-010, and the Pittsburg department, Dept. 54, has its own Zoom link on the small claims page. For any remote hearing, documents must reach the clerk in person, by drop box or by overnight delivery 3 court days ahead. The court won't take them electronically.
When the filing belongs in Martinez instead, the Wakefield Taylor drop box counts anything deposited between 8:00 a.m. and 5:00 p.m. as filed that day. Our Contra Costa County court filing page covers both buildings.
Antioch evictions, step by step
Landlords with Antioch rentals file the unlawful detainer in Pittsburg. The court's landlord-tenant page describes the pace. Under current state law the tenant has 10 court days to respond after personal service (the court's page still says 5 days), and if an Answer is filed, the court's page puts trial about 20 days after that. Only the Sheriff can carry out the lockout. A landlord can't change the locks, remove belongings or shut off utilities.
Speed at the start depends on what the server knows. For an Antioch eviction, send:
- the notice and the complaint packet as PDFs, up to 5 files;
- each adult occupant's name, spelled as on the lease;
- the complex name, building and unit, plus any gate code;
- the hours someone is usually home, if you know them;
- whether we should also file the complaint in Pittsburg or by eFiling.
Attorneys don't get a counter option here. Under Local Rule 2.87 and the Ninth Amended E-Filing Standing Order (Standing Order 3.2, dated February 2, 2026), unlawful detainer is one of the designated case types that represented parties must e-file, and has been since July 5, 2022. The same order covers civil, family law, probate, small claims and appeals. Self-represented landlords may still file at the window.
Papers to serve in Antioch?
Which Antioch ZIP Codes cross city lines?
Antioch's two main ZIP Code areas are mostly city land, but not entirely. From the Census Bureau's 2020 ZCTA to place relationship file:
- 94509 (the northern part of town): about 86% of its land is in Antioch. The rest is unincorporated, apart from a small piece of Pittsburg.
- 94531 (the southern part): about 89% is in Antioch, and the rest is unincorporated.
- 94513: Brentwood's ZIP Code area also takes in about 1.4 square kilometers of Antioch.
- 94561 and 94565: small slivers of Antioch fall in the Oakley and Pittsburg ZIP Code areas.
So an Antioch house can carry a Brentwood, Oakley or Pittsburg mailing address, and a 94509 address can sit outside the city. For service, the street address on the papers is what we use. For venue, the court's table works by city, and Antioch, Brentwood, Oakley and Pittsburg all land at the same Pittsburg courthouse for evictions and small claims.
Serving Antioch commuters
Antioch BART, at 1600 Slatten Ranch Road, is a terminal station. BART says it connects to Pittsburg/Bay Point using diesel multiple unit trains, with a transfer platform between Pittsburg/Bay Point and Pittsburg Center. On weekdays, BART's posted schedule shows the first southbound train from Antioch leaving before 5 a.m.
If the person commutes to Concord, Walnut Creek, Oakland or San Francisco, the house may be empty from before dawn until evening. A server who tries only at midday could miss them all week. Tell us when the person usually leaves and gets home, whether they work weekends, and where they work. With a work address, we can try a lobby or a parking lot as well as the front door.
This matters more after January 1, 2027. Under AB 747, the diligence needed before leaving papers with someone else at the home or business is shown by at least 3 personal delivery attempts, on 3 different days at 3 different times (CCP § 415.20(b)(2)). Each attempt will also need a photo stamped with the date, time and GPS location (CCP § 417.10). Our AB 747 guide explains the full rule.
Serving a company with an Antioch storefront
A manager at an Antioch shop or restaurant usually can't accept papers for the company. Look up the business on the California Secretary of State's bizfile Online and copy the exact entity name and its agent for service of process. That agent may be a commercial registered agent in another city entirely.
Send the agent's details with the papers. If you want an officer tried as well, name the officer. Our serving corporations guide explains who can accept for a corporation or LLC. It also explains what happens when the listed agent can't be found.
What if the person has moved out of Antioch?
Tenants leave and debtors move. If an Antioch address comes back stale, skip tracing can look for a current one. Give us the last known address, a phone number, an employer, a vehicle or a relative nearby. We send the result to you, and with your go-ahead the papers go back out for service.
For copies from an existing case, such as an earlier proof or a judgment, see document retrieval. For the rules on who may serve papers in California, see our guide. We make no guarantees for service.
Nearby East County cities
Nearby cities we serve, with their courthouse and ZIP Code details:
- Brentwood, 5.1 miles away
- Oakley, 5.7 miles
- Pittsburg, 6.1 miles, home of the Arnason Justice Center
- Clayton, 7.8 miles
- Concord, 11.2 miles
For the whole county, see Contra Costa County process servers.