Police 10-codes are numeric brevity codes (10-4 = message received) used on law-enforcement radio; NATO prowords like ROGER and WILCO do the same job on military nets. Codes vary by agency — always confirm local usage.
Police 10-Codes: General Reference
These are commonly encountered interpretations compiled across agencies, not an operational codebook for a named department. Confirm meanings against your agency’s current published procedures. The sourced Tucson example below illustrates differences.
Are military radio codes the same as police 10-codes?
No single police 10-code list is a universal military standard. Police numeric codes depend on the agency; military radio procedures use their own prescribed terminology. This page separates agency examples, radio procedure words, and informal phrases.
For example, Tucson publishes 10-4 as an acknowledgment and 10-20 as location. In aviation, ROGER acknowledges receipt, while WILCO also expresses understanding and compliance. Tucson police codes · FAA: ROGER · FAA: WILCO.
FEMA recommends clear, shared terminology for emergency communication. Read FEMA guidance.
Why the agency matters
These examples are specific to Tucson. In particular, 10-52 differs from the ambulance-request meaning in the general reference.
| Code | Meaning in Tucson |
|---|---|
| 10-4 | Acknowledgment |
| 10-10 | Available to take calls |
| 10-20 | Location |
| 10-33 | Disturbance |
| 10-52 | Traffic collision involving injury |
| 10-59 | Ambulance |
| 10-99 | Officer needs urgent help |
Source: City of Tucson radio signal codes. Checked 12 September 2026.
Status Codes: Agency-Dependent Examples
Status codes are not universal. For instance, Tucson uses Code 1 for a confidential message, rather than the routine-response interpretation shown in this general list. Tucson’s published definitions.
California Penal Code References
Selected California statute numbers, not universal police radio codes. These short labels are summaries; consult the California Penal Code for the statute and its scope.
Radio Prowords
Procedures depend on the service. The FAA Pilot/Controller Glossary defines aviation usage; do not treat every informal radio term as a NATO-standard proword.
| Proword | Meaning |
|---|---|
| BREAK | Separates long messages without ending transmission |
| COPY | Message received and understood |
| CORRECTION | Error in previous transmission — correction follows |
| DO NOT ANSWER | Do not reply to this message |
| I SAY AGAIN | Intentionally repeating previous transmission |
| MORE TO FOLLOW | Additional information coming |
| NEGATIVE | No / Disagreement / Request denied |
| OUT | Transmission finished; no response expected |
| OVER | End of transmission — reply expected |
| READ BACK | Repeat this transmission verbatim back to me |
| RELAY TO | Forward to named station |
| ROGER | Acknowledges receipt of the last transmission |
| SAY AGAIN | Repeat your last transmission |
| SILENCE x3 | All stations cease transmission immediately |
| SILENCE LIFTED | Normal communication may resume |
| VERIFY | Check and confirm the information |
| WILCO | Will comply — implies Roger, never use together |
Informal Military Phrases
These expressions are informal usage examples, not a substitute for service-specific communications procedures.
Military Acronyms
Use the procedure for your radio service
Use the prescribed phrase when asking for a message again. In aviation, SAY AGAIN requests repetition; ROGER acknowledges receipt and WILCO adds a commitment to comply. Required readbacks still apply. FAA terminology.
New Zealand and other jurisdictions
The general US examples above do not establish New Zealand Police procedure. Consult the relevant agency’s published instructions for local use.
Spell clearly, then practice
Use the NATO phonetic alphabet chart and converter to spell a callsign. Review military and Zulu time for time references. The practice quiz uses the general reference meanings, so it is a study aid rather than agency qualification.