Reverse 911

About Reverse 911

REVERSE 911® is an outbound notification system which may be used for time-sensitive, mass distribution of emergency messages.  The system is particularly effective in times of crisis when rapid communication to a targeted group of citizens or emergency responders is critical.   Citizens may be given information regarding evacuation notices, hazardous material releases, community-policing activities or alerts to boil water if necessary.   Therefore, when residents receive a REVERSE 911® message, it is important to listen carefully and follow all instructions provided in the alert. 

It is also important for residents not to rely on REVERSE 911® notifications as their only means of emergency information.  The system may be used in conjunction with information provided to the media, directions given by emergency responders, and information posted on official city, county and government websites.

The REVERSE 911® system is able to send notifications to landline telephones, TTY phones, cellular phones, Voice Over Internet Protocol phones, and email/text addresses. Currently, the Ventura County REVERSE 911® database includes both listed and unlisted landline phone numbers for AT&T and Verizon customers.  Residents who want to receive notifications on their cellular, TTY or VoIP phones will need to register online or call the Ventura County Sheriff’s Office of Emergency Services at 805-648-9283.

About the System

System Capabilities

The Ventura County Reverse 911® system has the ability to deliver outbound voice, text and e-mail messages to residents during emergencies using a combination of database and GIS (Geographic Information Systems) technologies.

Message Delivery Rate

Using the on-site bank of 46 telephone lines, the Ventura County Reverse 911® system has the ability to place up to 5,520 calls per hour and up to 240,000 calls per hour utilizing the off-site Mass Call™ lines.  Both time calculations are based on a 20-second voice message.

Participating Cities

Camarillo, Fillmore, Moorpark, Ojai, Oxnard, Port Hueneme, Santa Paula, and the unincorporated areas of Ventura County      

Intended Use

Evacuation notices, hazardous materials releases, community policing activities (AMBER alerts, endangered missing adults, prisoner escapes, high incidence of criminal activity, etc.), and public health emergencies

REVERSE 911® Telephone Database

The Ventura County Reverse 911® database currently includes both listed and unlisted landline telephone numbers, but does not include cellular, Voice Over Internet Protocol (VoIP), or TTY numbers.

Registration for Cellular, VoIP, or TTY Numbers

Residents may register phone numbers online, by mail or by calling the Ventura County Sheriff’s Office of Emergency Services Reverse 911® Public Information Hotline.

To register information online, please visit the County of Ventura website, click on the Disaster Information link and then on the REVERSE 911® logo.

Registration can also be mailed to:

Ventura County Sheriff’s Office of Emergency Services
800 South Victoria Avenue #3450
Ventura, California 93009

The Ventura County Reverse 911® Public Information Hotline will be staffed Monday through Friday from 8 am to 5 pm. The telephone number to call is 805-648-9283.

REVERSE 911® Caller ID

The telephone number that may be displayed on resident’s Caller ID device depends upon the geographic area from which calls originate. The three possible phone numbers are 805-517-1510 (Ventura County Government Center), 805-639-3004 (East Valley Sheriff’s Office) or 866-849-3243 (Mass Call™). These numbers are for outbound calls only.  Residents with questions or requesting additional information should call the Ventura County Reverse 911® Public Information Hotline at 805-648-9283.

REVERSE 911® Manufacturer

Indianapolis-based Sigma Communications    

Special Information

Residents who would like to add an e-mail address to associate with their landline telephone may email Reverse 911 services. Please include the telephone number, contact name, and email address.