10 42 Police Code
10 42 Police Code details, meaning for the police force is End Duty.
The 10-42 Police Code is a widely used law enforcement signal meaning “End of Duty” or “Officer Ending Tour of Duty.” This specific code is commonly used by police officers and emergency dispatchers to signify that an officer has completed their shift and is signing off from service. It’s a respectful and efficient way to communicate that an officer is going off duty, especially in radio transmissions and law enforcement records.
In some solemn contexts, 10-42 is also used during memorials or end-of-watch ceremonies to honor fallen officers who have died in the line of duty. When broadcast ceremonially, it represents their final sign-off, marking a heartfelt moment of respect and remembrance within the police community.
On this page, you’ll find accurate, free, and regularly updated information about the 10-42 police code meaning, as well as a growing list of other police 10 codes, cop codes, law enforcement signals, and officer dispatch codes used across various departments nationwide. Whether you’re a civilian curious about police lingo, a journalist covering law enforcement, or a law student looking to learn more about radio codes, we’ve got the resources to help.
The 10-42 Police Code is one of the most widely recognized radio codes used by police officers and law enforcement agencies across the United States and even internationally. It holds the specific meaning of “Ending Duty” or “Officer Signing Off”, and is typically used at the conclusion of a shift. You may have come across this code while listening to a police scanner, watching real-life law enforcement shows, or reading about police radio communication protocols.
Like many other 10-codes, the 10-42 police signal plays a critical role in maintaining concise and standardized communication over two-way radios, which are prone to interference and background noise. Officers and dispatchers will often pronounce this code clearly, digit-by-digit—“Ten-Four-Two”—to ensure clarity and prevent any confusion during live transmissions. Clear pronunciation is especially important in high-stress or emergency situations where miscommunication can lead to delays or errors in response.
The development of the police 10-code system, including 10-42, dates back to the late 1930s and early 1940s. It was originally created to help streamline communication for law enforcement personnel operating over early radio systems. In 1974, the Association of Public-Safety Communications Officials-International (APCO) formally expanded and standardized these codes, giving departments across the country a shared language for efficient message transmission. This advancement helped reduce radio traffic confusion and made cross-jurisdiction communication far more effective.
The 10-42 code also carries a symbolic meaning within police culture. In solemn ceremonies, such as memorials for fallen officers, the final radio call may include a 10-42 transmission to signify that an officer’s duty has ended permanently—marking their end of watch. This tradition underscores the emotional significance of the code within the law enforcement community.
Police officers and law enforcement personnel rely heavily on specialized communication systems to carry out their duties efficiently and safely. One of the most critical tools they use is police radio codes, which are designed to convey complex information quickly and clearly over two-way radios. A great example of this is the 10-42 Police Code, which is used to signify “End of Duty”—a message commonly transmitted between a police officer and dispatch at the conclusion of a shift.
Communication between officers and dispatchers—the individuals responsible for coordinating emergency responses—is essential for maintaining law and order. Codes like 10-42 allow for fast and accurate updates on an officer’s status, especially in fast-paced situations where time and clarity are of the essence. Instead of using full sentences that could be misunderstood due to background noise or radio interference, officers say, “10-42” to efficiently communicate that they are signing off duty. This shorthand helps reduce confusion and streamline the flow of radio traffic during active operations.
Police codes, including 10-42, do more than just help officers report to dispatch. They also enable seamless communication between different branches of law enforcement. Officers use these codes to coordinate with other patrol units, detectives, special task forces, local jail staff, and even inter-agency responders. This shared language improves collaboration and response time, especially during emergencies where multiple units must act in unison. Whether reporting a status update, requesting backup, or informing others of a situation, these codes eliminate ambiguity and promote clear, standardized responses.
The system of 10-codes, like the 10-42 Police Code, has been a cornerstone of police communication for decades. Originally developed to make radio transmissions faster and more effective, these codes have evolved into an essential part of daily police work across the United States and in many other countries. By using standardized terminology, officers can maintain operational control, ensure the safety of fellow responders, and provide timely support to the public.
Were you trying to find accurate, up-to-date information on the 10-42 Police Code or any other law enforcement communication code, but came up empty-handed? If so, you’re in the right place. We understand how difficult it can be to locate trustworthy explanations for police codes, radio signals, and law enforcement shorthand—especially since many of these codes vary by state, county, or even department.
Our mission is to make these police radio codes and cop signal meanings accessible to everyone—from civilians and students to journalists, researchers, and emergency response professionals. Whether you’re looking for the meaning of 10-42 (End Duty) or trying to decode another lesser-known police term you heard on a scanner, TV show, or during an incident, we’re here to do the legwork for you.
If you couldn’t find the police code you’re looking for—be it 10-42 or any other—we invite you to reach out using the comments form located at the bottom of this page. Submit your question or request, and we’ll respond promptly with researched, verified, and clear explanations. Our support is completely free, with no cost to you.
What is 10 42 Police Code?
The 10-42 Police Code is a standard radio communication signal used by police officers and law enforcement personnel across the United States and in various international agencies. Specifically, the code “10-42” means “End of Duty” or “Officer is Signing Off”. It is used to indicate that a police officer has completed their shift and is officially ending their tour of duty.
This code is typically transmitted over the police radio system to dispatchers and other units in the field. When an officer says “10-42”, it is a formal notification that they are no longer available for calls or patrol and are finishing their assigned work period. This helps maintain clear communication and situational awareness within the police force, especially in high-activity areas or during multi-officer operations.
Beyond its practical use in daily operations, the 10-42 code holds deeper significance in the police community. In memorial services and end-of-watch ceremonies, “10-42” is often broadcast one final time in honor of an officer who has died in the line of duty. It serves as a symbolic way of marking the final sign-off of a fallen officer, and it is a powerful, respectful tribute within law enforcement traditions.
If you’re listening to a police scanner, watching police reality shows, or reading about law enforcement protocols, understanding what 10-42 means can give you valuable insight into how police officers communicate using 10-codes. These short, standardized codes are designed to enhance efficiency, reduce miscommunication, and keep radio traffic as clear and concise as possible.
What Do Police Codes Mean?
Have you ever found yourself listening to a police scanner or catching bits of dialogue on a cop TV show, only to hear cryptic numbers like 10-4, 10-42, or Code 3? These are part of what’s known as police radio codes—a specialized form of communication used by law enforcement to transmit vital information quickly, clearly, and securely. But what do these codes actually mean?
Police codes are a set of numeric signals or phrases designed to keep radio transmissions brief, standardized, and efficient. Instead of saying full sentences, officers use short codes to relay complex messages without cluttering the airwaves. These codes may seem confusing to the general public, but they are a crucial part of maintaining order, coordinating emergency responses, and ensuring officer safety.
If you’ve ever listened in on a cop radio, police dispatch channel, or public safety scanner, you’ve probably heard terms like “10-20” (location), “Code Red” (emergency), or “10-42” (end of duty). Many of these codes were created decades ago and are still used by agencies today, although they may vary slightly between states or jurisdictions. Some codes are known universally—like “10-4” meaning “message received”—while others are kept intentionally vague or confidential for security reasons.
To help demystify these police codes, we’ve found a fantastic resource that breaks it all down in a simple and visual format. Watch the video linked below to discover the top police radio codes, what they really mean, and how they’re used in real-world law enforcement scenarios. Whether you’re a true crime fan, future law enforcement officer, or just curious about how police communicate, this video is a must-watch.
Watch Now:
Explore the hidden language of law enforcement and finally understand what those mysterious codes mean when you hear them on the radio.
Selected Police Codes
10 4 Police Code
107 in Police Code
10 7 Police Code
10 80 Police Code
108 Police Code
10 8 Police Code
10 99 Police Code
11 10 Police Code
126 Police Code
245 Police Code
31350 Police Code