Most police codes are strictly practical — a plate check, a location request, a traffic stop. 10-42 starts out that way too, meaning simply that an officer is ending their shift. But it has taken on a second meaning that gives it more weight than almost any other code in law enforcement: it’s the code used to mark an officer’s final sign-off, including the last radio call for an officer who has died. This article explains both meanings, the tradition behind the ceremonial version, and why 10-42 occupies such a particular place in police culture.
The short answer: 10-42 means “ending tour of duty.” In everyday use it’s how an officer signals the end of their shift. In its ceremonial use, a “final 10-42” honours an officer at the close of their career or, most solemnly, at their end of watch after a line-of-duty death.
The Everyday Meaning of 10-42
In routine radio traffic, 10-42 is unremarkable. When an officer reaches the end of their shift — the end of their “tour of duty,” in the language many departments use — they let dispatch know they’re going off duty. Depending on the agency, that sign-off might be a 10-42, or a related code like 10-7 (out of service) or 10-10 (off duty), since this is one of those meanings that varies between departments. Dispatch logs it, the officer’s unit comes off the active board, and the shift is closed out.
That’s the plain version, and it’s the meaning you’ll hear most often on a working channel. An officer finishing a night shift calls in, clears their last assignment, and goes 10-42. Nothing dramatic — just the administrative bookend to a day’s work, the counterpart to going 10-8 (in service) at the start of the shift.
Like every police code, its exact number isn’t universal. Some agencies use 10-42 specifically for end of tour; others fold that meaning into a different code and use 10-42 for something else. The “ending tour of duty” sense is the widely recognised one, but as with all ten-codes, it pays to anchor the meaning to the agency broadcasting it. For the broader picture of how these codes work and why they vary, our overview of US police codes sets the scene.
The Ceremonial Meaning: End of Watch
The reason 10-42 is worth an article of its own is its second life as a ceremonial code. In law enforcement, an officer’s death in the line of duty is described as their “end of watch” — the moment their watch, their period of duty, comes to a permanent close. The phrase carries the idea that policing is a continuous watch kept over a community, and that an officer who dies on duty has stood that watch to the very end.
At police funerals and memorial services, a tradition known as the “Last Radio Call” or “Final Call” gives this idea voice. A dispatcher reads the fallen officer’s name and call sign over the radio, often calling for them several times. When no answer comes, the dispatcher formally clears the officer from service — frequently with a final 10-42, marking that this officer has ended their tour of duty for the last time. The transmission is usually followed by a short tribute noting the officer’s years of service and their end of watch date. For everyone listening — fellow officers, family, the community — it’s among the most moving moments in the entire memorial.
The same gesture is sometimes used to honour an officer retiring after a long career. On their final shift, colleagues and dispatch may mark a ceremonial last 10-42, closing out decades of service with the same code that closed out each ordinary day. In that setting the tone is celebratory rather than mournful, but the symbolism is shared: a career of watches, now complete.
Why This Code Carries So Much Weight
It might seem strange that a routine administrative code became the vehicle for law enforcement’s most solemn tribute, but that’s exactly what gives it its power. 10-42 is the code an officer uses at the end of every ordinary shift, thousands of times across a career. Turning that everyday sign-off into a final, unanswered call transforms the familiar into the profound. The community of officers who have gone 10-42 at the end of countless shifts hears, in the final call, the permanent version of a gesture they know intimately.
The tradition also reflects how deeply the radio itself sits at the centre of police work. For officers, the radio is a lifeline — the thread that connects them to their colleagues and to help throughout every shift. A tribute delivered over that same radio, in the same codes used every day, speaks in the native language of the profession. It says goodbye in the idiom of the job itself.
Because of this, 10-42 has become one of the codes that people outside law enforcement recognise and feel, even without knowing the rest of the system. Memorial pages, remembrance events, and organisations dedicated to fallen officers frequently reference the end of watch and the final call, and the code has come to stand for sacrifice and remembrance in a way few pieces of radio shorthand ever do. For how codes like this fit within the larger catalogue, our US police code category and the master police code lists page are useful references.
10-42 Among the Status Codes
To see 10-42 in its everyday context, it helps to place it beside the other status codes that track an officer’s availability through a shift. These are the codes that mark the rhythm of a working day:
| Code | Common meaning |
|---|---|
| 10-8 | In service / available for calls |
| 10-7 | Out of service |
| 10-6 | Busy / stand by |
| 10-23 | Arrived on scene |
| 10-42 | Ending tour of duty / end of shift |
Read together, they trace an officer’s day from the moment they go 10-8 at the start to the 10-42 at the end. The ceremonial final call simply takes the last of these and gives it a permanence it was never designed to carry, which is precisely what makes it land. For the deeper history and structure of the ten-code system these belong to, see our US 10-codes guide.
A Note on Variation and Respect
Because police codes vary by department, the specific code used in a final call isn’t identical everywhere. Some agencies use 10-42 for the end of watch tribute; others use 10-7 (out of service), 10-10, or a locally significant code, and many pair it with the officer’s badge or unit number. What’s consistent isn’t the exact digits but the gesture: a last call, unanswered, followed by a formal clearing from service and a note of the officer’s end of watch. The meaning lives in the ritual, not in a single universal number.
If you encounter references to 10-42 in the context of a memorial, it’s worth treating the code with the seriousness the tradition intends. For officers and their families, the end of watch is not radio trivia — it’s the formal marker of a life given in service. Understanding what the code means adds weight and context to those moments rather than reducing them to jargon.
Why Understanding 10-42 Matters
For scanner listeners, knowing 10-42 helps you follow the ordinary flow of a shift and recognise when a channel shifts into a memorial. For writers and journalists, using the code accurately — both its plain and ceremonial senses — lends authenticity and avoids the flattening that comes from treating all codes as interchangeable technical noise. And for anyone simply curious about police culture, 10-42 is a window into how a profession built on routine and procedure expresses something as human as grief and remembrance through the tools of the job.
The plain meaning and the ceremonial meaning aren’t really separate. The tribute works precisely because the code is so ordinary the rest of the time. Every ordinary 10-42 at the end of a shift is a small promise that the officer will be back tomorrow. The final 10-42 is the moment that promise closes — and that’s why a routine sign-off became the way law enforcement says its most difficult goodbye.
Using Police Code to Explore Further
Police Code is a global police code explorer that keeps meanings like these in one organised, searchable place — including the codes that carry cultural weight as well as the everyday ones. Instead of piecing together the plain and ceremonial senses of a code from scattered sources, you can look them up in context and see how usage differs across agencies. It’s free to browse and built for scanner listeners, journalists, writers, and anyone who wants to understand not just what police codes say, but what they mean. This piece touches on line-of-duty deaths; if the subject is a difficult one for you personally, it’s okay to step away, and support is available through people and services you trust.