California tenant guide

How To File An Unlawful Detainer In California

A source-backed guide to how to file an unlawful detainer in california, including what to check, documents to gather, and when to get professional review.

Published July 23, 2026 · Updated July 23, 2026 · By EvictionHelpAI Editorial

How To File An Unlawful Detainer In California

If you are trying to understand how to file an unlawful detainer in California, the basic process is: make sure the required notice rules were followed, prepare the court forms, file them in the correct superior court, pay the filing fee or ask for a fee waiver, and then have the summons and complaint served correctly.

California courts describe an unlawful detainer as an eviction court case. One court explains that it is “an accelerated method for recovery of possession of leased premises.” California courts also make clear that a landlord cannot remove a tenant without going through the court process. Only the Sheriff can carry out the eviction after the legal process is completed.

This article gives legal information, not legal advice. If any detail in your case is unusual, confirm it with the official California Courts Self-Help materials or get professional review before filing.

What how to file an unlawful detainer in california usually means

In practice, this usually means starting a formal eviction case in superior court after the required notice period has run.

California court guidance says the case is started by:

  1. Filing a complaint
  2. Having a summons issued
  3. Serving the complaint and summons on the defendant

For many residential cases, the complaint form used is Complaint - Unlawful Detainer (UD-100). California Courts Self-Help also says to start the eviction case by filling out court forms that include:

You will generally file in the superior court in the county where the rental property is located, and you should use the courthouse that handles evictions. Because local filing locations can differ, verify the exact courthouse with your county court before you go.

What to check first

Before filing, make sure the case is actually ready to file.

First, California courts say landlords must follow all statutory eviction requirements and any applicable local ordinances. That means the notice step matters. Court materials say an unlawful detainer proceeding is usually started by serving a 3-day notice or 30-day notice, though the UD-100 form itself includes several notice types, including 3-day, 30-day, 60-day, perform-or-quit, and other listed notice categories.

Second, make sure the notice deadline has passed before you file. California Courts Self-Help explains that:

The official forms and self-help pages should be your final check on how to count time in your situation. If you are unsure which notice applies, confirm that before filing rather than guessing.

Third, confirm whether your case fits the form you plan to use. The UD-100 form states: “Do not use this form for evictions after sale (Code Civ. Proc., section 1161a).” If your situation involves a post-foreclosure or sale-based eviction, review the official court materials carefully before filing.

Documents and facts to gather

California Courts Self-Help says to gather the records that support the eviction before you file. That commonly includes:

You should also be ready to identify all tenants and occupants you want listed in the case. The court guidance specifically says to list all tenants and occupants.

For the filing packet, California Courts Self-Help says to prepare the forms, copies, and proof for filing with the clerk. A practical checklist includes:

One additional detail on the complaint: the UD-100 form says that for residential property, a copy of the written agreement is required to be attached unless the form’s exception box is checked. If you do not know whether the attachment requirement applies in your case, review the current form instructions and official court guidance before filing.

Common mistakes to avoid

A few problems come up often.

Filing before the notice period ends.
If the deadline has not fully run, the filing may be premature. Double-check the counting rules on the California Courts Self-Help page.

Using the wrong court.
The case usually belongs in the superior court in the county where the rental is located, and at the courthouse that handles evictions.

Leaving out tenants or occupants.
The self-help guidance says to list all tenants and occupants. Missing someone can create service or enforcement problems later.

Not attaching needed documents.
If the complaint requires a copy of the written rental agreement, make sure it is included unless an exception on the form applies.

Assuming the filing fee is always the same.
California Courts Self-Help says the fee is usually $240 to $450, and that the amount generally increases when more past-due rent is requested.

Skipping the fee waiver option.
If you cannot afford the filing fee, California court guidance says you can ask for a fee waiver.

Overlooking service rules after filing.
Filing the case is not the end of the process. The summons and complaint still must be served correctly. Response timing can vary based on how service happened. California Courts Self-Help says a tenant’s answer deadline depends on the service method, so confirm the current rule with the official source and your local court.

When to get professional help

It is smart to get professional review before filing if:

That review can matter because unlawful detainer cases move quickly, and the court process depends on correct notice, correct forms, and correct service.

If cost is a concern, review the California Courts information on fee waivers to see whether you may qualify for help with filing fees.

Primary sources