Police Scanner Codes: Complete 10-Code Reference

Education
14 min read 3,800 words Police Radio Encryption Editorial Team

Police 10-codes are shorthand radio signals used by law enforcement to communicate quickly. This guide covers the most common codes—but remember: if your local police have encrypted their communications, knowing these codes won't help you hear anything.

Important: Codes Vary by Department

There is no universal 10-code standard. While some codes like 10-4 are nearly universal, many codes mean different things in different jurisdictions. The codes listed here are the most common interpretations, but your local department may use different meanings.

This variation is one reason many departments have switched to plain language per federal recommendations—codes can cause dangerous confusion during multi-agency emergencies.

Most Common 10-Codes

These are the codes you'll hear most frequently on police scanners. The top 10 are worth memorizing if you're new to scanning.

10-4 Acknowledged / Message received The most recognized radio code in the world
10-20 Location / What is your location? "What's your 20?" is common slang
10-8 In service / Available for calls Officer is ready to respond
10-7 Out of service Officer is unavailable (break, off duty)
10-99 Officer needs help / Emergency All available units respond
10-76 En route Traveling to a location
10-23 Arrived at scene On location at call
10-22 Disregard / Cancel Call is cancelled
10-33 Emergency traffic Clear the channel for emergency
10-50 Traffic accident Vehicle collision

Complete 10-Code List

Below is a comprehensive list of 10-codes organized by category. Use the filter to find specific types of codes.

Code Meaning Category
10-1 Receiving poorly / Unable to copy status
10-2 Receiving well / Signal good status
10-3 Stop transmitting status
10-4 Acknowledged / Message received status
10-5 Relay message status
10-6 Busy / Stand by status
10-7 Out of service status
10-8 In service / Available status
10-9 Repeat / Say again status
10-10 Fight in progress incident
10-11 Dog case / Animal problem incident
10-12 Stand by / Visitors present status
10-13 Weather and road conditions info
10-14 Prowler report incident
10-15 Prisoner in custody incident
10-16 Domestic disturbance incident
10-17 Meet complainant action
10-18 Complete assignment quickly action
10-19 Return to station action
10-20 Location / What is your location? info
10-21 Call by telephone action
10-22 Disregard / Cancel action
10-23 Arrived at scene status
10-24 Assignment completed status
10-25 Report in person action
10-26 Detaining suspect incident
10-27 License/registration check info
10-28 Vehicle registration check info
10-29 Check for wanted info
10-30 Unnecessary use of radio status
10-31 Crime in progress incident
10-32 Person with gun incident
10-33 Emergency traffic emergency
10-34 Riot / Major disturbance incident
10-35 Major crime alert incident
10-36 Correct time info
10-37 Investigate suspicious vehicle action
10-38 Stopping suspicious vehicle action
10-39 Urgent - use lights and siren emergency
10-40 Silent run - no lights/siren action
10-41 Beginning tour of duty status
10-42 Ending tour of duty status
10-43 Information info
10-45 Dead body / Fatality incident
10-50 Traffic accident incident
10-51 Wrecker needed action
10-52 Ambulance needed emergency
10-53 Road blocked info
10-54 Livestock on road incident
10-55 Intoxicated driver incident
10-56 Intoxicated pedestrian incident
10-57 Hit and run incident
10-58 Direct traffic action
10-59 Convoy or escort action
10-60 Squad in vicinity info
10-61 Personnel in area info
10-62 Reply to message action
10-63 Prepare to copy status
10-64 Message for local delivery info
10-65 Net message assignment info
10-66 Message cancellation action
10-67 Clear for net message status
10-68 Dispatch information info
10-69 Message received status
10-70 Fire alarm emergency
10-71 Advise nature of fire info
10-72 Report progress on fire info
10-73 Smoke report info
10-74 Negative / No status
10-75 In contact with status
10-76 En route status
10-77 Estimated time of arrival info
10-78 Need assistance emergency
10-79 Notify coroner action
10-80 Chase in progress incident
10-81 Breathalyzer test action
10-82 Reserve lodging action
10-83 Work school crossing action
10-84 If meeting... advise ETA info
10-85 Delayed due to... status
10-86 Officer on duty status
10-87 Pick up / Distribute checks action
10-88 Present telephone number info
10-89 Bomb threat emergency
10-90 Bank alarm emergency
10-91 Pick up prisoner action
10-92 Improperly parked vehicle incident
10-93 Blockade action
10-94 Drag racing incident
10-95 Prisoner in custody incident
10-96 Mental subject incident
10-97 Check signal / Arrived at scene status
10-98 Prison break emergency
10-99 Officer needs help / Emergency emergency
10-100 Restroom break status

NATO Phonetic Alphabet

Police use the NATO phonetic alphabet to spell out letters clearly over radio. This prevents confusion between similar-sounding letters like "B" and "D" or "M" and "N."

A Alpha
B Bravo
C Charlie
D Delta
E Echo
F Foxtrot
G Golf
H Hotel
I India
J Juliet
K Kilo
L Lima
M Mike
N November
O Oscar
P Papa
Q Quebec
R Romeo
S Sierra
T Tango
U Uniform
V Victor
W Whiskey
X X-ray
Y Yankee
Z Zulu

Example Usage

A license plate like "ABC 123" would be called out as:
"Alpha Bravo Charlie, one two three"

Other Common Police Terms

Signal Codes

  • Signal 7 — Dead body (varies by region)
  • Code 1 — Respond at your convenience
  • Code 2 — Respond urgently, no lights/siren
  • Code 3 — Emergency response, lights and siren
  • Code 4 — No further assistance needed

Status Codes

  • Copy — Message received and understood
  • Clear — Finished with assignment
  • Dispatch — Central communications center
  • Unit — Individual officer or patrol car
  • Beat — Patrol area

Vehicle Descriptions

  • RP — Reporting party (person who called)
  • GOA — Gone on arrival
  • UTL — Unable to locate
  • BOLO — Be on the lookout
  • APB — All points bulletin

Crime Abbreviations

  • DUI/DWI — Driving under influence
  • 459 — Burglary (California code)
  • 211 — Robbery (California code)
  • 187 — Homicide (California code)
  • ADW — Assault with deadly weapon

California Penal Codes

In California and some other states, you'll hear numeric codes referring to penal code sections. A "211 in progress" means a robbery is happening. These vary entirely by state and are not related to 10-codes.

The Shift to Plain Language

Why Departments Are Abandoning Codes

Following recommendations from the Department of Homeland Security and lessons learned from disasters like Hurricane Katrina, many departments have moved to plain language for routine communications.

Problems with Codes

  • Codes vary between departments
  • Cause confusion in multi-agency responses
  • New officers must memorize hundreds of codes
  • Misunderstandings can be dangerous

Benefits of Plain Language

  • Universal understanding
  • No training needed to understand
  • Clearer communication
  • Fewer errors in emergencies

Note: Many departments still use 10-codes for routine status updates (10-8, 10-7) while using plain language for incident descriptions.

The Bigger Problem: Encryption

You can memorize every 10-code perfectly, but if your local police department has encrypted their communications, you won't hear any of them. Encryption makes scanner codes irrelevant.

40%+ Major U.S. cities have encrypted
100% Encryption blocks all codes
0 Ways for the public to listen

Learning codes won't help if there's nothing to hear. Check if your area is encrypted before investing time in memorizing codes.

Why are police encrypting? →

Frequently Asked Questions

What does 10-4 mean?

10-4 means 'Acknowledged' or 'Message received.' It's the most widely recognized police code and is used to confirm that a message has been understood.

What does 10-20 mean on a police scanner?

10-20 means 'What is your location?' or is used to report a location. 'What's your 20?' is commonly used in police, trucking, and citizen band (CB) radio communications.

Are police 10-codes the same everywhere?

No. While some codes like 10-4 are nearly universal, many 10-codes vary significantly between departments. A 10-33 might mean 'Emergency' in one jurisdiction and 'Clear the air for emergency traffic' in another. Many departments are moving to plain language.

Why do police use codes instead of plain language?

Historically, codes saved air time and provided some operational security. However, studies show codes cause dangerous confusion during multi-agency responses. Many departments now use plain language per federal recommendations.

Can I still learn police codes if my area is encrypted?

You can learn codes, but if your local police have encrypted their communications, you won't be able to hear them use these codes—encryption makes scanners useless regardless of your knowledge.

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