Calling 911: What to Expect

Denver 911 logoDenver 911 operators are trained to ask questions that will help you get the assistance you need as quickly as possible. It is important to stay on the line with your 911 operator until you receive instructions to hang up.  If you are in danger, you may be instructed to leave the building, secure yourself in a room, or take other protective actions.


When Should I Call 911?

Only call 911 for the following reasons:

  • To stop a crime
  • To report a fire
  • To save a life

Learn more about what to expect when calling 911. For all other concerns, call our non-emergency line at (720) 913-2000.

What's the non-emergency line?

Call this number to report the following:

  • Any crime to a person not life-threatening
  • Burglary to a home not in progress
  • Auto theft not in progress
  • Parking complaints
  • Loud music complaints

Common Questions & Answers

What questions will the 911 operator ask?

  • What is your current location?
  • What is your phone number?
  • What is happening?
  • When did the incident occur?
  • Are there injuries?
  • Can you describe any suspicious persons or vehicles?
  • Do you want contact from officers?

How long will it take for officers to respond?

Officers always try to respond as quickly as possible; however, there are a number or factors that determine how long you may wait for an officer to respond. For instance, the number of incidents and priority of calls could delay the officer from responding to your incident immediately. The type, and priority of calls determine the response time as will the number of available officers in your neighborhood.

Can I request an estimated time of arrival?

While it is reasonable to want to know how long it will take for an officer to respond, there are several logistical and operational barriers that make it difficult for call-takers to provide citizens with an estimated time of arrival (ETA). 

Due to the dynamic of constantly changing call volume, officer availability cannot be precisely estimated. Some calls may be resolved in just a few moments, while others require more thorough investigation and could take hours to complete.

How are calls processed?

When you call for assistance, whether you are reporting an emergency or a non-emergency situation, your incident is entered into our Computer Aided Dispatch System (CAD) for tracking purposes.  We verify your address, obtain your contact numbers, create a short summary of what is happening, determine the nature of incident, and assign a priority ranking to the call. These priority rankings are established by the Denver Police Department.

How are 911 calls prioritized?

Call volume in the 911 Communications Center fluctuates through the day. At any time, we can receive numerous high--priority calls, or perhaps a single call requiring multiple-officer response. Emergency calls always take priority and are dispatched first. Priority rankings are established by the Denver Police Department.

Why were officers diverted while responding to my call?

Officers are sometimes diverted from lower-priority calls to respond to higher-priority emergencies. This process ensures safety for our citizens and Denver’s first responders, but may increase the response time for lower-priority calls. 

Denver Police Officers are also diverted to assist Denver Health Paramedics handling medical emergencies and the Denver Fire Department at large scale fire emergencies.

What happens if I accidentally dial 911?

If you mistakenly reach 911, please do not hang up before the 911 Operator answers the phone. The information from your phone still enters our system. If you aren’t on the phone when the Operator answers, she or he will call you back. The time spent calling people back who have inadvertently dialed 911 takes time away from people who need emergency help.

What do i do if I'm having VoIP issues with 911?

VoIP subscribers enjoy certain advantages like free long distance, or cheaper options for local and cellular phone services. However, VoIP calls present problems for 911 answering systems and can often be routed to the wrong 911 center or be accidentally dropped.

In addition, because VoIP is transmitted over the Internet, the caller’s associated number often cannot be recognized by emergency 911 systems. The 911 system provides Automatic Number Information (ANI) and Automatic Location Information (ALI) which is rendered virtually useless for VoIP users.

Precautionary Measures

VoIP subscribers should take precautionary steps to ensure their safety when emergency services are needed.  

  • Keep a land line telephone installed in your house with minimal services so that you can still receive 911 services.
  • Keep a land line or have a back up for power outages or Internet difficulties.
  • Know the 911 capabilities of your VoIP provider—they have their own features and abilities pertaining to 911. 
  • Upon signing up for your VoIP, register the physical location from where the phone will be used so it can be entered into your local 911 system.
  • When you move, re-register your phone with the new address—it may take your VoIP provider some time to transfer this information to your 911 system.
  • Do not use VoIP for 911 while mobile—the center you call will only be provided with the address you have registered.
  • Attempt to test your VoIP through your local 911 center during slow times of the day—get this approved with your 911 center first.
  • Keep your family informed of your VoIP limitations and procedures.

What do I do if i have cell phone issues with 911?

Wireless cell phones can be an important public safety tool, but they also create a unique challenge for public safety and emergency response personnel in locating the caller. The precise location of a caller who dials 911 from any cell phone cannot be determined. Therefore, it is essential that you stay on the line and clearly give your location to the 911 Operator

A wireless phone is actually a radio with a transmitter and a receiver that uses radio frequencies or channels  (instead of telephone wire) to connect callers. Because wireless phones are by their very nature mobile, they are not associated with one fixed location or address.

The Federal Communications Commission (FCC) has taken a number of steps to increase public safety by coordinating development of a nationwide, seamless communications system for emergency services that includes the provision of location information for wireless 911 calls. This effort has been implemented in three phases: Phase 0, Phase I, and Phase II. 

Wireless Phase II, in effect now, requires carriers to provide far more precise location information - within 50 to 300 meters (approximately 170 to 1000 feet).  The cell phone vendors have different methods in which the cellular phone handset can provide the latitude and longitude for the caller, either through triangulation, GPS or a hybrid of the two. Denver is compliant with Phase II; however, your cell phone must also be compliant to obtain more detailed location data.