Wireless Public Alerting (WPA)

Alert Ready is a service designed to deliver critical and potentially life-saving emergency alert messages to Canadians.

The Alert Ready system was developed in partnership with federal, provincial, and territorial emergency management officials, Pelmorex Corp., the broadcast industry, and wireless service providers to ensure you receive emergency alerts immediately and know when to take action to keep you and your family safe. 

Beginning in April 2018, all wireless service providers will have the capability to distribute emergency alerts received from alerting authorities directly to consumers’ WPA-compatible wireless devices using Cell Broadcast distribution.

Wireless service providers will only receive and relay messages that are issued for threat-to-life situations.

Emergency alerts intended for wireless devices are issued to a defined geographic area, which can be as small as a few city blocks, so that only people in the defined area receive the emergency alerts.  The defined area is selected by the alerting authorities. Compatible wireless devices in the targeted area will receive the emergency alerts within seconds of alert issuance, provided the phones are powered on and connected to the LTE cellular network.

You cannot opt out of receiving threat-to-life emergency alerts.

Emergency alerts begin with a distinct sound, known as the Canadian Alert Attention Signal. Emergency alerts sent to compatible wireless devices may also cause the phone to vibrate.

On compatible wireless devices, the emergency alert will display an “EMERGENCY ALERT/ALERTE D’URGENCE” banner, followed by text that describes the situation and provides instructions on what actions to take and where to find more information. At the top of each emergency alert, the issuing government agency will be clearly indicated.

If you are a person with a sight, or hearing disability: Alternate formats can be issued, but not every alerting authority or every device will have the capacity to produce alternate formats. For emergency alerts distributed via compatible wireless devices, emergency alerts may be read to the recipient if their device supports this accessibility feature. The vibration feature that accompanies emergency alerts sent to compatible wireless devices will help to make hearing impaired people aware of the alerts.

Federal, provincial, and territorial governments are responsible for issuing emergency alerts. 

Federally, emergency alerts are issued most frequently by Environment and Climate Change Canada.

Each provincial or territorial government decides who will have the authority to issue alerts within their jurisdictions. For example, emergency alerts could be issued by provincial or territorial emergency management offices or in some cases by municipal emergency management offices or local police and fire departments.

Media companies, including television, radio stations, cable and satellite distributors, as well as websites receive these emergency alerts and relay them to their consumers.

Beginning April 6, 2018, wireless service providers will be capable of distributing emergency alerts received from alerting authorities directly to their consumers’ compatible wireless devices connected to LTE networks using Cell Broadcast distribution.

The Alert Ready system allows alerting authorities from federal, provincial and territorial governments to issue a wide range of public safety messages. However, broadcasters and wireless service providers are only required to distribute emergency alerts for situations that pose an immediate threat-to-life.

Government officials developed and agreed on a specific list of the types of alerts that are considered a threat-to-life and should be distributed immediately, interrupting radio and television broadcasts. These “Broadcast Immediately” emergency alerts have the highest level of severity, urgency and certainty. For a full list, visit the Alert Types section of the AlertReady.ca.

Issuing alerts outside of this list (for example heavy rainfall or blizzard warnings) is at the discretion of each of the broadcasters. Wireless service providers will only receive and relay messages that are issued for threat-to-life situations. 

Yes. The alerting authority determines what areas are affected by an incident, weather or environmental situation, and uses a standard system that will typically correspond with municipal, regional or provincial boundaries. The standardized system will allow participating radio, television, cable and satellite companies to broadcast the emergency alerts that are most relevant to the communities they serve.

Emergency alerts intended for wireless devices are issued to a defined geographic area, which can be as small as a few city blocks, so that only people in the defined area receive the emergency alerts. Compatible wireless devices in the targeted area will receive the emergency alerts within seconds of being issued, provided the phones are powered on and connected to the LTE cellular network.

No. In order for emergency alerts to be received on a wireless device three conditions must be met.

The wireless device must be:

  • An LTE-device like a smartphone (LTE is commonly referred to as “4G LTE”); and
  • Wireless public alerting (WPA)-compatible; and
  • Connected to an LTE cellular network at the time the emergency alert is issued or joins the network while the alert is still active.

A wireless device that is WPA-compatible is:

  • an LTE-device; and
  • has special software embedded in it which allows for messages sent by your service provider, via Cell Broadcast, to be received in the standard Alert Ready format.

Emergency alerts that meet the Alert Ready format allow you to know when an alert is received (because of the sound and vibration), and also provides confirmation that it is issued by a legitimate source.

Visit the Wireless section of AlertReady.ca to find a link to the section of your wireless service provider’s website that provides information on compatible devices.

No. While the emergency alert may look like a text message it is not a text message.

Emergency alerts are sent via Cell Broadcast distribution. Cell Broadcast is a mobile technology that allows messages to be broadcast to all compatible wireless devices within a designated geographical area. Cell Broadcast is designed for simultaneous message delivery to multiple users in a specified area and is not affected by network congestion because it uses dedicated part of the network, different from that used for traditional voice and data traffic.  

Cell Broadcast can be compared to radio broadcast. Radio towers broadcast music to people in defined geographic areas as long as the individuals can pick-up the broadcast signal and have their radios turned on. Similarly, Cell Broadcast messages are delivered to those compatible wireless devices that are within range of cell towers and antennas in the designated area.

Wireless service providers are required to distribute Emergency alerts to compatible smartphones that can access LTE (cellular) networks. Additional wireless devices – such as tablets and wearable accessories (e.g. smartwatches) – may be capable, from a technical perspective, to receive some form of the message, but it will not necessarily be received on the device in the Alert Ready format.

For information on compatible wireless devices offered by your wireless service provider, visit the Wireless section of AlertReady.ca.

Emergency alerts will not end or terminate a voice call or data session in progress.

If you are on a voice call when the emergency alert is received, you will be made aware of the alert by a notification tone (similar to call waiting). When your call terminates the alert will be displayed on your wireless device.

If you are on a data session, the emergency alert will briefly interrupt your data session will continue but it may be briefly interrupted by the emergency alert appearing on your wireless device screen.

A compatible wireless device that is turned off, or is in Airplane Mode, will not display an emergency alert. If the emergency alert is still active when the wireless device is powered on, and the user is still in the alert area, the wireless device will then display the alert.

A compatible wireless device that is set to silent will display an emergency alert, but you might not hear the emergency alert sound. The emergency alert sound will usually play at whatever the current volume setting is on the wireless device, so if your wireless device is set to silent, no sound will accompany the emergency alert message. However, this behaviour can differ depending on your wireless device and in some instances the alert sound may override your user settings.

If the emergency alert is still active when the compatible wireless device is turned back on, and you are within the emergency alert area, the emergency alert will be displayed.  If the emergency alert is no longer active or if you have travelled outside of the alert area, it will not be displayed.

While on Wi-Fi, if the compatible wireless device can still communicate with the LTE cellular network, it will receive emergency alerts. If the wireless device is not within reach of the LTE cellular network (or is set to Wi-Fi only) it will not receive an emergency alert.

Test alert messages will be identified as such. These messages are intended to “test” the functionality of the system, and inform consumer of wireless emergency alerts, and do not require the consumer to take steps to secure their safety.

You may be required to acknowledge receipt of the emergency alert in order to allow for your wireless device to resume normal functioning. In the event that you cannot acknowledge the alert, the alert sound and vibration will continue for 8 seconds. Depending on your specific wireless device, additional reminders may occur.

Upon receiving the emergency alert, it is important to take action safely. Stop what you are doing when it is safe to do so and read the emergency alert. Government officials will include, within the emergency alert, the information you need for any action you need to take. This could include but is not limited to: limit unnecessary travel, evacuate the areas, seek shelter, etc. 

It is important to take action safely, especially if the emergency alert is received while operating a vehicle. If you are driving, it is important to remain calm and pull over at your earliest opportunity to view the emergency alert.  


Wireless alerts are sent on a specific cellular channel that is separate from normal text and data traffic. While the alerts may look like text messages, they are not text messages and are not billed like text messages.

Also, emergency alerts are sent to wireless devices in a specific geographic area and do not require the phone numbers of those devices. As such there is no ability to identify or bill for the messages that are received.

No. Emergency alerts received on your compatible wireless device are relevant to you and require immediate attention, and government regulations mandate that all compatible wireless devices receive all relevant alerts.

Unlike radio and television broadcasting, which often has broad areas of coverage; wireless public alerting is geo-targeted and can be very specific to a limited area of coverage. As a result, if an emergency alert reaches your wireless device, you are located in an area where there is an imminent danger.

Yes. Emergency alerts are issued to a defined geographic area, such that only people in the defined area will receive the emergency alerts. If you are travelling and happen to be in another province when an emergency alert is issued, your compatible wireless device will receive the emergency alert within seconds of being issued, provided your phone is powered on and connected to the LTE cellular network.


No. If you are travelling, you will only receive emergency alerts that occur where you are.

Canadians can keep track of emergency alerts occurring in specific areas (e.g. where they or other family members live) through a number of available apps and online services.

Emergency alerts are broadcast from cellular towers and antennas within the area specified by the alert issuer. Compatible wireless devices connected to the specified towers/antennas will receive the emergency alert. The towers/antennas therefore must be operational to send emergency alerts. If you are in an affected area but your wireless device is unable to connect to any towers/antennas because of the situation, you will not receive the emergency alert on your wireless device. 


No. Emergency alerts are sent using Cell Broadcast distribution. Cell Broadcast can only transmit information to your wireless device. This means that no data is being gathered about you, your wireless device or your location when emergency alerts are sent out.