NATIONAL 10-4 Day
National 10-4 Day on October 4th honors CB radio culture, truckers, travelers, and one of America’s most recognized radio phrases: “10-4,” meaning message received.
NATIONAL 10-4 DAY | OCTOBER 4
National 10-4 Day celebrates the language of the open road, the golden age of CB radio, and the truck drivers who helped make “10-4” part of everyday conversation.
When someone says “10-4,” they are saying the message has been received and understood. It is short, clear, and to the point. That is exactly why it worked so well over two-way radios, where quick communication could help drivers share road conditions, report hazards, ask for help, or simply keep each other company on a long stretch of highway.
#NATIONAL10-4DAY
CB radio, short for Citizens Band radio, gave everyday people a way to communicate over short distances. Long before cell phones, GPS apps, and instant traffic alerts, CB radios helped motorists connect with other drivers nearby. Truckers used them to share information about accidents, weather, construction, traffic delays, and road safety. They also used them to build community across lonely miles.
For many people, CB radio brings back the sounds of handles, channels, rubber ducks, smokeys, and good buddies. It was a language all its own, and it rolled right into American pop culture.
During the 1970s, trucking and CB radio became part of movies, television, and music. Films and shows like Smokey and the Bandit, Convoy, White Line Fever, Movin’ On, and B.J. and the Bear helped introduce the wider public to trucking culture. The open road became a symbol of freedom, grit, humor, independence, and community.
National 10-4 Day also recognizes the serious side of CB radio. While the slang and pop culture may get the spotlight, CB radio has long served a practical purpose. Drivers used it to alert others to danger, call for help, and pass along information when it mattered most. In emergencies, a simple message received at the right time could make all the difference.
Today, “10-4” has moved far beyond CB radio. People use it in conversation, texts, workplaces, and everyday life to say, “Got it.” It is one of those rare phrases that crossed from radio code into common language, and it still carries the same meaning: message received.
COMMON CB RADIO TERMS
CB radio developed a colorful language that reflected the personality of the road. A few familiar terms include:
10-4 — Message received or understood.
Breaker — A request to join a channel or conversation.
Handle — A CB radio nickname.
Good buddy — A friendly term for another radio user.
Smokey — A highway patrol officer or law enforcement vehicle.
What’s your 20? — Where are you located?
Hammer down — Keep moving or press on.
Rubber duck — The lead vehicle in a convoy.
Like any living language, CB slang could vary by region, driver, and era. That was part of the fun. It gave the road its own voice.
HOW TO OBSERVE NATIONAL 10-4 DAY
Celebrate National 10-4 Day by learning more about CB radio history and the truckers who helped shape American road culture. Watch a classic trucking movie, listen to a truck-driving song, or ask someone who used a CB radio to share their favorite story.
Thank a truck driver for the work they do keeping goods moving across the country. Learn a few classic CB radio terms and try using “10-4” when you want to say, “message received.”
You can also take a drive, visit a truck stop, support a transportation museum, or share memories of CB radios, road trips, and family travel.
Use #NationalTenFourDay to share on social media.
NATIONAL 10-4 DAY HISTORY
The phrase “10-4” comes from the system of radio ten-codes used to make communication faster and clearer. Over time, “10-4” became one of the best-known codes, commonly understood to mean acknowledgment, message received, or OK.
On October 2, 1978, President Jimmy Carter issued a 10-4 Day statement recognizing October 4, 1978. In the statement, Carter noted the importance of Citizens Band radio for highway safety, emergency communication, and companionship. He also joined CB organizations across the country in celebrating “10-4 Day.”
National Day Calendar added National 10-4 Day after a submission from Albert, who helped bring renewed attention to the observance in 2012. The day honors the history of CB radio, America’s trucking community, and a phrase that still means exactly what it always has.
10-4. Message received.
Related days on the National Day Calendar:
NATIONAL TRUCK DRIVER APPRECIATION DAY
NATIONAL ROAD TRIP DAY
NATIONAL RADIO DAY
NATIONAL WALKIE TALKIE DAY