If you’ve listened to a Texas scanner or watched a trooper make a traffic stop, you’ve heard the shorthand: “10-4,” “10-50,” “show me 10-8.” These are ten-codes, the numbered radio signals Texas law enforcement uses to pass information quickly without tying up the channel. This guide lays out the codes used across Texas, who uses them, and the catch that trips up most people: a 10-code in Texas can mean something completely different one state over.
The short version. Texas agencies, led by the Department of Public Safety, mostly use the APCO-style ten-code set. The single most common code is 10-4, meaning “acknowledged” or “message received.” But there’s no law forcing every Texas department onto an identical list, so always treat the meanings below as the widely accepted versions rather than gospel for every county.
Where Ten-Codes Came From
Before getting into the Texas specifics, it helps to know why these codes exist at all. They were developed in the late 1930s by Charles Hopper, a communications director for the Illinois State Police, working with what became the Association of Public-Safety Communications Officials (APCO). Early radios had a real technical limitation: the first fraction of a second of any transmission often got clipped before the equipment fully keyed up. Prefixing messages with the spoken word “ten” gave the radio a beat to engage, so the important number that followed actually made it through. The brevity was a bonus on channels where airtime was scarce.
That origin matters for Texas because the codes you hear today are descendants of that original APCO list, adapted over decades by Texas agencies to fit their own needs. The bones are national; the details are local.
How Policing and Radio Work in Texas
Texas runs a layered law enforcement system, and the radio traffic reflects it.
Texas Department of Public Safety (DPS) is the statewide agency. It splits Texas into six regions with communications centers anchored in Dallas, Houston, Weslaco, El Paso, Lubbock, and San Antonio, plus a presence at the Capitol in Austin. DPS has migrated to a P25 digital radio network that can link any communications center in the state, so a trooper can in principle reach any other trooper statewide. One quirk of that linked system: when a dispatcher transmits, they may broadcast over many sites at once, while the trooper in the field is only heard on their local site. A scanner listener some distance away can sometimes hear only the dispatcher’s half of a conversation as a result.
Within DPS sit several divisions. The Texas Highway Patrol (THP) is the most visible — the troopers enforcing traffic law on the highways and interstates. The Texas Rangers are the oldest state law enforcement agency in the country with statewide jurisdiction, organised into lettered companies and tasked with major investigations, public corruption cases, and cold cases. There’s also a Criminal Investigations Division, the Commercial Vehicle Enforcement unit that weighs and inspects trucks, and the Texas Division of Emergency Management, which coordinates the state’s disaster response and reports to the Governor.
Below the state level, every county elects a sheriff who runs the county’s law enforcement, and cities run their own municipal police departments — Houston PD, Dallas PD, San Antonio PD, Austin PD, Fort Worth PD, El Paso PD, and hundreds of smaller ones. Each of these can set its own radio protocol. Texas Highway Patrol frequently shares county sheriff radio systems out in the rural parts of the state where they operate, which is one reason codes have drifted toward a common core even without a formal mandate. When troopers and deputies share a channel day after day, their vocabularies converge. For the broader national picture of how these systems developed, our overview of US police codes is a useful companion.
Texas Police 10-Codes (The Complete List)
Here are the ten-codes commonly used by Texas DPS and many Texas agencies. Meanings can shift between departments, so verify locally if accuracy matters for your purpose.
| Code | Meaning | Code | Meaning |
|---|---|---|---|
| 10-1 | Unable to copy/change location | 10-50 | Traffic accident |
| 10-2 | Signal good | 10-51 | Wrecker needed |
| 10-3 | Stop transmitting | 10-52 | Ambulance needed |
| 10-4 | Acknowledged / OK | 10-53 | Road blocked |
| 10-5 | Relay message | 10-54 | Livestock on highway |
| 10-6 | Busy, stand by | 10-55 | Intoxicated driver |
| 10-7 | Out of service | 10-56 | Intoxicated pedestrian |
| 10-8 | In service / available | 10-57 | Hit and run |
| 10-9 | Repeat/say again | 10-58 | Direct traffic |
| 10-10 | Out of service (subject to call) | 10-59 | Convoy or escort |
| 10-12 | Stand by (officials present) | 10-60 | Squad in vicinity |
| 10-17 | En route | 10-70 | Fire alarm |
| 10-18 | Urgent | 10-71 | Advise nature of fire |
| 10-19 | Return to station | 10-76 | En route to call |
| 10-20 | Location | 10-77 | Estimated time of arrival |
| 10-21 | Call by telephone | 10-78 | Need assistance |
| 10-22 | Disregard | 10-80 | Pursuit in progress |
| 10-23 | Stand by / arrived at scene | 10-85 | Delayed |
| 10-24 | Assignment complete | 10-86 | Operator on duty |
| 10-27 | Driver’s license check | 10-87 | Pick up / distribute checks |
| 10-28 | Vehicle registration check | 10-88 | Advise present phone number |
| 10-29 | Check for wants/warrants | 10-89 | Bomb threat |
| 10-30 | Danger/caution | 10-90 | Bank alarm |
| 10-32 | Person with a gun | 10-91 | Pick up prisoner/subject |
| 10-33 | Emergency traffic only | 10-93 | Blockade |
| 10-36 | Correct time | 10-94 | Drag racing |
| 10-37 | Suspicious vehicle | 10-95 | Prisoner in custody |
| 10-38 | Traffic stop | 10-96 | Mental subject |
| 10-39 | Run with lights and siren | 10-97 | Arrived at scene |
| 10-40 | Run silent (no lights/siren) | 10-98 | Jail break |
| 10-43 | Information | 10-99 | Records indicate wanted/stolen |
Suffixes, Severity, and the Code System: Texas Layers On Top
A detail worth knowing: Texas often attaches a severity suffix to 10-50 (traffic accident). You’ll hear “10-50F” for a fatal crash, “10-50I” for an accident with injuries, and “10-50PD” for property damage only. That single letter tells responding units whether they need an ambulance and a supervisor or just a report and a wrecker, which shapes the entire response before anyone arrives.
Texas departments also borrow the Code response system that sets how an officer travels to a call. Code 1 is a routine response at normal speed. Code 2 is prompt but without lights and siren. Code 3 is the full emergency run with lights and siren. On top of that, you may hear “Signal 100” used to mean emergency traffic only — everyone else clear the air so a critical situation can be handled without interruption. This stacking is normal: a dispatcher might send a unit “Code 3 to a 10-50F” and then call “Signal 100” to keep the channel clear. For the deeper history of where the numbered codes came from, see our guide to US police radio 10-codes.
The Texas Codes You’ll Hear Most
While there are nearly a hundred codes on the books, the day-to-day reality of a Texas patrol channel runs on a much smaller set. A handful come up constantly:
- 10-4 — acknowledgment. The verbal nod that a message landed.
- 10-20 — location. “What’s your 10-20?” means “where are you?”
- 10-38 — a traffic stop. The trooper announces the stop and the plate before approaching.
- 10-28 and 10-29 — running a plate and checking for wants or warrants, the routine that precedes most stops.
- 10-50 — a wreck, usually with the F/I/PD suffix attached.
- 10-8 and 10-7 — in service and out of service, the bookends of a shift and the most frequent status calls of all.
A typical stop sounds like a short, efficient sequence. A trooper sees a vehicle, calls in “10-38” with the location and reads the plate phonetically for a “10-28.” Dispatch returns the registration. The trooper may run the driver’s licence with a “10-27” and check for warrants with a “10-29.” If everything’s clean, the trooper finishes and goes “10-8,” back in service. That cluster of half a dozen codes carries most of what fills a Texas channel on an average day.
The Phonetic Alphabet Texas Officers Use
When a trooper reads a licence plate or a surname, similar-sounding letters get confused over a noisy channel, so officers spell using the NATO phonetic alphabet.
| Letter | Word | Letter | Word | Letter | Word |
|---|---|---|---|---|---|
| A | Alfa | J | Juliett | S | Sierra |
| B | Bravo | K | Kilo | T | Tango |
| C | Charlie | L | Lima | U | Uniform |
| D | Delta | M | Mike | V | Victor |
| E | Echo | N | November | W | Whiskey |
| F | Foxtrot | O | Oscar | X | X-ray |
| G | Golf | P | Papa | Y | Yankee |
| H | Hotel | Q | Quebec | Z | Zulu |
| I | India | R | Romeo |
A plate reading ABC-123 goes out as “Alfa-Bravo-Charlie, one-two-three.” It sounds formal, but it removes the guesswork between letters like B, D, and V that are nearly impossible to tell apart through static. The alphabet is the same one used by aviation and the military worldwide, which is exactly why it works so well across agencies that otherwise share no common code list.
Why a Texas 10-Code Isn’t Universal
Here’s the part people get wrong. Ten-codes feel like a national standard because of television, but they aren’t. The APCO published a recommended list back in 1940, and almost no agency adopted it exactly. There are roughly 18,000 law enforcement agencies in the United States, each operating with a good deal of independence, and the result is a patchwork. The differences can be more than an inconvenience — they can be dangerous.
The classic example: a Texas officer’s “10-50” means a traffic accident. In parts of Louisiana, “10-50” means officer down. During large multi-agency events — hurricanes along the Gulf, manhunts, pursuits that cross jurisdictions — those mismatches cost time and create real risk. The communication breakdowns during Hurricane Katrina in 2005, when officers from different jurisdictions literally could not understand each other’s radio traffic, pushed federal agencies to recommend plain language for anything involving multiple agencies under the National Incident Management System. Mexico, just across the Texas border, built its own separate código system rather than adopting American ten-codes at all, and our breakdown of Mexico’s police codes shows how differently a neighbouring country approached the same problem.
So in Texas today you’ll find a hybrid landscape. Smaller rural sheriff’s offices that rarely work outside their own county tend to keep the full code list, because the codes are efficient and everyone on their channel knows them. Larger agencies lean on plain language for cross-agency work while keeping codes for routine internal traffic. The codes haven’t disappeared, but they share the channel with plain English far more than they used to, and the balance keeps shifting.
Tips for Scanner Listeners and Newcomers
- Start with the core dozen. 10-4, 10-20, 10-38, 10-28, 10-29, 10-50, 10-7, and 10-8 will carry you through most Texas traffic.
- Listen for suffixes. “10-50F” tells you far more than “10-50” alone, and the F/I/PD letters change the whole picture of a crash.
- Note the agency. A city PD, a county sheriff, and DPS on the same scanner may not use identical meanings, so identify who’s talking before you trust a definition.
- Track the response code too. Whether a unit is sent Code 1, Code 2, or Code 3 tells you how serious the call is even before you decode the rest.
- Don’t assume TV is right. Shows invent codes or borrow them from the wrong jurisdiction for dramatic effect.
- Cross-check anything that matters. Many Texas agencies publish their own code sheets, and a single reliable reference beats guessing.
Using Police Code to Explore Further
Police Code is a global police code explorer built to make exactly this kind of lookup quick. Instead of piecing together a code’s meaning from scattered forum posts and outdated PDFs, you can search a single organised database that covers states, agencies, and countries side by side. Whether you’re a scanner hobbyist trying to follow your local feed, a journalist verifying what a code meant in a report, a writer chasing authenticity for a script, or someone studying for a dispatch role, the platform keeps codes, signals, and the legal references behind them in one place. Our master police code lists page and the dedicated US 10-codes category are good starting points for browsing, and from there you can branch out into the agencies and states that border or compare to Texas.
The bottom line for Texas is straightforward. Learn the dozen codes that do the heavy lifting, pay attention to suffixes and response codes that carry hidden detail, always anchor a code to the agency that broadcast it, and treat any single list — including this one — as the common baseline rather than an unbreakable rule. Do that, and the chatter on a Texas scanner stops sounding like a secret language and starts sounding like exactly what it is: a fast, practical shorthand built for people who can’t afford to waste a word.