TL;DR
Knowing how to call 911 can save valuable time during a medical emergency. Learn what information to give the dispatcher, how Enhanced 911 (E911) works, why mobile phones and VoIP systems can present location challenges, and what you should do while waiting for EMS to arrive. Clear communication and quick action can make a critical difference.
Every Second Counts During an Emergency
Calling 911 is something that most people hope they will never need to do, but in an emergency, knowing what to do can save valuable time. If someone is experiencing a heart attack, severe bleeding, choking, a stroke, or another life-threatening emergency, a calm and accurate call to 911 will help emergency responders get to the right place with the right information.
Many people assume calling 911 is as simple as dialing three numbers. But in reality, dispatchers rely on the information you provide to determine the priority of the emergency, dispatch the appropriate responders, and give life-saving instructions until help arrives.
This guide explains how to call 911, what information to provide, how Enhanced 911 (E911) works, the challenges of calling from mobile phones and VoIP services, and what you should do while waiting for emergency medical services (EMS).
When Should You Call 911?
Call 911 whenever someone has a serious or life-threatening injury or sudden illness, or when immediate emergency assistance is needed.
Examples include:
- Cardiac arrest
- Non-responsive or unconscious
- Chest pain or signs of a heart attack
- Difficulty breathing
- Symptoms of a stroke, including sudden weakness, facial drooping, or difficulty speaking
- Severe bleeding
- Bleeding that won’t stop
- Serious burns
- Major trauma from a vehicle crash or fall
- Seizures lasting several minutes or repeated seizures
- Suspected poisoning with severe symptoms
- Drowning
- Any situation where someone’s life or safety is in immediate danger
If you’re not sure whether the situation is an emergency, it’s generally better to call. The 911 dispatcher can help determine the appropriate response.
Stay Calm Before You Speak
It’s natural to panic during an emergency, but taking one deep breath before speaking can help you communicate more clearly.
The dispatcher’s first priority is determining:
- What type of emergency
- Where the emergency is
- What happened
- Is anyone is in immediate danger
- What type of responders are needed
Answer questions directly and avoid talking over the dispatcher.
What to Tell the 911 Dispatcher
Providing clear, accurate information helps responders prepare before they arrive. Be ready to tell the dispatcher:
Your Exact Location
Always provide:
- Street address
- Apartment, suite, or room number
- Location within the building if indoors
- Business name if applicable
- Nearby intersections or landmarks if outdoors
Never assume the dispatcher automatically knows your location.
Describe What Happened
Briefly explain the emergency.
For example:
- “A man collapsed and isn’t breathing.”
- “My mother has severe chest pain.”
- “A child is choking.”
- “Someone has been badly injured in a car accident.”
Provide a concise and factual description. Avoid long stories and explanations.
Describe the Patient
Tell the dispatcher:
- Approximate age
- Sex
- Responsive or unresponsive (unconscious)
- Pulse or signs of circulation
- Breathing normally or not
- Major injuries or symptoms
If CPR has already started, let the dispatcher know immediately. For example: “I have a male victim, approximately 70 years old, who is not responsive and not breathing. CPR has been started.”
Answer Every Question
Dispatchers often follow structured protocols that may seem repetitive, but every question serves a purpose.
They may ask:
- Is the patient responsive?
- Is the patient breathing?
- When did symptoms begin?
- Is anyone performing CPR?
- Is the scene safe?
- Is there significant bleeding?
First responders are often dispatched while you are still answering questions.
Don’t Hang Up
Unless instructed otherwise, stay on the phone.
The dispatcher may:
- Provide CPR instructions
- Provide First Aid instructions
- Coach you through helping someone who is choking
- Explain how to control severe bleeding
- Tell you how to safely position the patient
- Update responding crews with new information
You can
- Provide updated information
- Let EMS know of any changes to the patient’s condition
- Help guide EMS to your location
Remaining on the line can help save a life.
What Is Enhanced 911 (E911)?
Enhanced 911, commonly called E911, is a technology that helps dispatch centers identify a caller’s location more quickly.
Traditional landline phones automatically provide:
- The phone number
- The address and location where the phone is located
This allows dispatchers to locate callers even if they cannot speak.
Enhanced 911 systems may also receive location information from wireless carriers and certain internet-based phone services.
However, the information isn’t always perfectly accurate.
Calling 911 from a Mobile Phone
Most 911 calls today come from mobile phones. While mobile phones are more convenient, they do present unique challenges.
Unlike traditional landlines, cell phones are constantly moving.
Location information may be determined using:
- GPS signals
- Nearby cellular towers
- Wi-Fi positioning
- Device location services
Although modern smartphones are much more accurate than older phones, location data can still be affected by:
- VPN services that mask IP locations
- Disabled location services
- Large buildings
- Parking garages
- Rural locations
- Mountains
- Poor GPS reception
Always tell the dispatcher your location, even if you believe they already have it.
If you’re traveling on a highway, mention:
- Highway name/number
- Direction of travel
- Nearest exit
- Mile marker
- Visible landmarks
Challenges with VoIP 911 Calls
Voice over Internet Protocol (VoIP) phone systems, including many home and business internet phones, may not automatically provide your current physical location.
VoIP systems rely on users to enter their locations. When businesses use the same VoIP account for multiple locations, the system will not know which location is accurate.
911 services usually need to be enabled and configured on each VoIP account. Be sure to enter the correct information and keep the account up to date.
Anyone using VoIP should know:
- The exact street address where they’re calling from
- Their suite or office number
- Floor number if applicable
Never rely solely on the phone system to provide your location.
Texting 911
Many 911 systems support texting 911 when speaking isn’t possible.
Situations where texting would be beneficial include:
- Active shooter
- Domestic abuse
- Home invasion
- Situations where making noise would increase danger
If texting is available:
- Share your exact location first.
- Describe the emergency clearly and concisely.
- Answer all questions promptly.
- Keep messages brief.
Whenever it is safe to do so, calling remains the preferred option because dispatchers can obtain information much more quickly through voice communication.
What to Do While Waiting for EMS
Once EMS is on the way, your actions can make a difference.
Follow Dispatcher Instructions
Many dispatchers are trained to provide life-saving medical guidance.
They may instruct you to:
- Perform CPR
- Use an AED
- Help someone who is choking
- Control severe bleeding
- Assist with childbirth
- Position someone safely
Follow their instructions carefully until responders arrive.
Unlock Doors and Clear the Path
If possible:
- Unlock the front door.
- Turn on outside lights if it’s dark.
- Move pets into another room.
- Clear a path for stretchers and equipment.
- Have someone watch for the ambulance.
These simple steps can reduce delays.
Gather Important Information
If available, collect:
- Current medications
- Allergies
- Medical conditions
- Identification
- Insurance information
- Advance directives, if applicable
Don’t delay life-saving care to search for paperwork.
Keep the Patient Comfortable
Unless the dispatcher instructs otherwise:
- Stay with the patient.
- Keep them calm.
- Loosen tight clothing if breathing is difficult.
- Cover them with a blanket if they’re cold.
- Avoid giving food or drinks.
If the person becomes unconscious and stops breathing, begin CPR immediately if you are trained or follow dispatcher-assisted CPR instructions.
Send Someone Outside
When indoors, having someone meet EMS outside can help guide them to the patient and save valuable time.
Common Mistakes to Avoid
During an emergency, avoid these common errors:
- Hanging up too soon
- Assuming dispatchers know your exact location
- Driving yourself during a serious medical emergency when an ambulance is appropriate
- Forgetting apartment or suite numbers
- Ignoring dispatcher instructions
- Giving food or medication without guidance
- Leaving the patient alone
Why CPR and First Aid Training Matter
While EMS often arrives quickly, brain damage can begin within minutes after the heart stops beating. Immediate action by bystanders can make the difference between life and death. You can learn life-saving CPR and First Aid by taking a free class.
Learning CPR, how to use an AED (automated external defibrillator), and basic first aid prepares you to help during those critical first minutes before professional responders arrive.
Many workplaces, schools, childcare providers, healthcare offices, coaches, and community organizations encourage or require CPR certification because emergencies can happen anywhere.
Final Thoughts
In an emergency, knowing how and when to activate the EMS system is essential. Calling 911 is the first step in getting help, but what happens during those first few minutes also matters. Providing an accurate location, answering the dispatcher’s questions, and following their instructions while waiting for EMS can improve patient outcomes.
Today’s technology, such as Enhanced 911, has made locating callers faster and more accurate than ever before, but it isn’t perfect. Whether you’re calling from a landline, mobile phone, or VoIP service, never assume your location is automatically available. Clearly stating where you are remains one of the most important pieces of information you can provide.
Preparedness starts long before an emergency happens. Knowing how to call 911 and having CPR and first aid training can help prepare you to respond to an emergency with confidence.