When a tenant fails to pay rent in California, a landlord must serve a **3-Day Notice to Pay Rent or Quit** before filing an unlawful detainer. Here’s how to do it correctly, so courts and tenant attorneys cannot dismiss your case.

**1. Use the right notice.**

A 3-Day Notice to Pay Rent or Quit is used only for non-payment of rent. Make sure the notice lists the tenants’ names, property address, total past-due rent, and the exact amount demanded. Do not include late fees or other charges.

**2. Personal service.**

Under California law, the notice may be served **personally** by the landlord or any adult over 18. Hand the notice directly to the tenant at the rental property. This is the preferred method【851637488798805†L99-L115】.

**3. Substituted service.**

If the tenant is not home, serve the notice to a competent member of the household (age 18+) and then mail a copy to the tenant at the rental address. This is called **substituted service**; it is valid when personal service is unsuccessful【851637488798805†L117-L141】.

**4. Posting and mailing.**

If no one is available to accept service, **post the notice** on the front door or another conspicuous place and mail a copy to the tenant. This completes service, but the three-day period does not begin until the notice has been mailed【851637488798805†L117-L141】.

**5. Calculate the three days correctly.**

The three-day period starts the day **after** the notice is served and counts business days only. Weekends and court holidays are excluded.

**6. Keep proof of service.**

Document when and how you served the notice. Take photos of posted notices and keep mailing receipts. Courts require proof that the notice was properly served.

**7. File promptly after expiration.**

If the tenant does not pay or move out within three days, file your unlawful detainer. Attach a copy of the 3-Day Notice and proof of service to your complaint.

Following these steps ensures your notice is legally valid and minimizes defenses based on improper service.