California Preliminary Notice: Who Must Serve It, How It Works, and What Happens If You Miss It

The California 20-day preliminary notice is one of the most misunderstood requirements in construction law. Contractors assume the general contractor handles it. Suppliers assume notice isn't required for materials. Property owners assume they'll hear about a lien problem only at the last minute. All of these assumptions create expensive problems.

This is the definitive guide to California's preliminary notice requirement — what the law actually requires, who it applies to, how to serve it correctly, what happens when you get it wrong, and how it fits into the broader timeline of California lien rights. For the mechanics lien filing process itself, see the California mechanics lien guide.

What Is a California Preliminary Notice?

A California preliminary notice — formally governed by Civil Code §8200–8216 — is a written notice that a subcontractor, material supplier, or equipment lessor must serve on the property owner, the direct hiring party, and the construction lender (if any) within 20 days of first furnishing labor, services, equipment, or materials on a project.

The notice is not a lien. It does not claim any debt or create any cloud on title. It is a statutory alert — it tells the owner and lender, in plain terms: "I am working on or supplying this project, and I may have lien rights if I'm not paid."

Why the "20-day" Name Can Mislead

The notice is called a 20-day preliminary notice because it must be served within 20 days of first furnishing. But you can serve it after 20 days — you just lose protection for work done more than 20 days before the late service. A contractor who starts work January 1 and serves the notice February 15 can still lien for work done on or after January 26 (20 days before service). The work done January 1–25 is unprotected.

This "rolling 20-day" concept is critical. Most contractors who realize they forgot the notice assume they've lost everything. They haven't — at least not for recent work.

Who Must Serve the California Preliminary Notice?

Parties Who MUST Serve the Notice

Under Civil Code §8200, these parties must serve a preliminary notice to preserve lien rights:

• Subcontractors (any tier) who do not have a direct contract with the property owner
• Material suppliers who provide materials to anyone on the project except under a direct contract with the owner
• Equipment lessors who lease equipment for use on the project
• Certain laborers providing professional or licensed services who are paid other than as employees

Parties Who Do NOT Need to Serve the Notice

• The general contractor who has a direct contract with the property owner is NOT required to serve a preliminary notice
• Day laborers who are W-2 employees (their employer handles the lien rights question)
• The property owner themselves

What Happens If You Don't Serve the Preliminary Notice?

The consequences depend on who you are and when you catch the problem:

For subcontractors with no direct contract with the owner: If you never serve the notice, you have no mechanics lien rights for work performed more than 20 days before you do serve it. If a project is complete by the time you realize you missed it, you may have no lien rights at all.

For material suppliers: Same result — no notice, no lien protection for materials delivered more than 20 days before the notice date.

Can you still sue on the contract? Yes. The preliminary notice is a prerequisite for mechanics lien rights, not for all legal remedies. You can still sue the GC or the party that hired you for breach of contract. But a mechanics lien against the property is a much more powerful remedy, especially when the GC is struggling financially.

How to Serve the California Preliminary Notice

Who Receives the Notice?

Under Civil Code §8200, the notice must be served on:

1. The owner of the property (or reputed owner)
2. The general contractor or the direct hiring party
3. The construction lender or reputed construction lender, if any

Service Methods

Civil Code §8106 specifies acceptable service methods. You have three options:

1. Personal service — Hand-deliver a copy to the recipient. Get a signature acknowledging receipt.

2. First-class registered or certified mail, return receipt requested — Send to the recipient's business address or residence. The postmark date counts as the service date even if the mail is returned undelivered.

3. Overnight delivery by an express service carrier — Use FedEx, UPS, or similar. Keep the tracking confirmation.

What the Notice Must Contain

Under Civil Code §8102 and §8204, the preliminary notice must include:

• Claimant's name and address
• Name and address of the person who hired you
• Description of the labor, services, equipment, or materials you're providing
• Estimated value of the work (a good-faith estimate)
• Description of the jobsite (street address is sufficient)
• Name and address of the owner or reputed owner
• Name and address of the construction lender, if known

For residential projects, the notice must also include this verbatim statutory warning in at least 10-point bold type:

NOTICE TO PROPERTY OWNER: If bills are not paid in full for the labor, services, equipment, or materials furnished or to be furnished, a mechanic's lien leading to the loss, through court foreclosure proceedings, of all or part of your property being so improved may be placed against your property even though you have paid your contractor in full. You may wish to protect yourself against this consequence by (1) requiring your contractor to furnish a signed release by the person or firm giving you this notice before making payment to your contractor, or (2) any other method or device that is appropriate under the circumstances.

The Timing Rule in Detail

Serving on Time (Within 20 Days)

If you serve the notice within 20 days of first furnishing, you're protected from day one. Your potential lien can cover everything you do on the project from your first day through your last.

Serving Late

If you serve after day 20, you lose protection for work done more than 20 days before the service date.

Example: You start work March 1 but don't serve until April 15. Your protected window starts March 26 (20 days before April 15). All work March 1–25 is outside your lien protection. The decision to serve late rather than not at all is almost always the right one.

How the Preliminary Notice Fits Into the Full California Lien Timeline

1. Day 1: First furnishing — the clock starts
2. Day 20: Preliminary notice deadline (serve by this date for full protection)
3. [Last day of work]: Your last furnishing date — this is when the lien deadline clock starts
4. 90 days after completion/cessation: Deadline to record the mechanics lien (Civil Code §8412)
5. 30 days after recording the lien: Deadline to serve a copy of the lien on the owner
6. 90 days after recording the lien: Deadline to file a lawsuit to enforce the lien (Civil Code §8460)

For the complete breakdown of deadlines and how to file the lien itself, see the California mechanics lien guide. For the step-by-step process of serving the notice itself, see our step-by-step guide to serving the 20-day notice.

California Preliminary Notice FAQ

This is not legal advice. Consult a licensed California attorney for advice specific to your situation.