10-4 Roger That

10-4 Roger That: Understanding the Popular Radiocommunication Phrase

Radiocommunication has been an essential tool in communication, especially in the emergency services sector. To ensure effective communication, there is a need for clear and concise terms that transmit the message accurately. One of the widely used phrases in radiocommunication is “10-4 Roger That.” It is a phrase adopted by civilian and military personnel alike in the event of an emergency. It is a communication code used to show that a message has been received and understood. In this article, we will dive deeper into the “10-4 Roger That” phrase, its origin, and how it is used today.

What Does 10-4 Mean?

The term “10-4” in radiocommunication slang means “message received.” It implies that the receiver has understood the message and has no questions regarding the instructions or facts delivered. Similarly, it can also mean, “Yes, I understand,” or “That’s correct.” It is a quick response to let the sender know that the message has been received and understood on the other end. It is often used in situations that require immediate responses, such as emergency response operations.

Where Did 10-4 Roger That Originate?

The origin of 10-4 Roger that is shrouded in mystery, but it has been used in aviation and military communication since the 1940s. Back then, radios were not as sophisticated as they are today, making communication challenging. For instance, distance and external interference could cause message loss or create a communication gap between the sender and the receiver.

The military found it necessary to create communication codes that were meant for specific purposes. These codes were also applicable to prevent enemy forces from understanding what was being said. They used the term “Roger” instead of “Received.” This could be traced back to the Second World War, where Allied forces used” Roger and Out” in their communication. For instance, a pilot would say,” Roger” when receiving a transmission and “Out” to end communications.

Similarly, the term “10” is believed to have been adopted from the police force communication system. It is a series of codes that the police used to communicate with the station or other units in the field. The term “10” referred to a category of messages that had a particular meaning. For instance, “10-4” meant, “Stop transmitting on this channel and listen to me.”

Today, the phrase “10-4 Roger That” has been widely adopted and used to communicate in various sectors, including police, fire departments, security, aviation, road transport, and industrial operations. It is used where a quick response is essential and used to establish a clear communication link.

Essential 10-4 Roger That Radiocommunication Guidelines

For effective communication, using clear and concise terms is essential, especially in emergency situations. Here are some of the essential 10-4 Roger that radio communication guidelines:

1. Speak Slowly and Clearly

For communication to be effective, speak slowly and clearly, especially in environments with background noise. By speaking slowly, you give the receiver ample time to understand the message, and speaking clearly ensures that the message is transmitted accurately.

2. Give the Sender Acknowledgment

After receiving a transmission, acknowledge the sender using the 10-4 Roger That phrase. This lets the sender know that you have received and understood the message, and prevents the sender from repeating the message.

3. Use the Correct Terminology

Radiocommunication requires the use of proper terminology to ensure everyone understands each other correctly. Using the wrong terms can result in miscommunication and costly mistakes.

4. Make Your Message Concise

It is essential to make your message concise to avoid misunderstanding or misinterpretation of the instructions given. Take time to formulate a clear message that can be easily understood by the receiver.


The “10-4 Roger That” phrase has been around for decades and has been used in different communication sectors. It is a code used to show that a message has been received and understood. Whether you are a military officer, a police officer, an aviation personnel or an industrial worker, it is a phrase you are likely to encounter. To ensure effective communication, it is essential to use clear and concise terms and adhere to the essential 10-4 Roger That radio communication guidelines. By doing so, you can ensure that the message is received and understood on the other end.