Ten-code

Ten codes, or 10-codes, are used in two-way voice radio communication as verbal numeric shorthand for frequently used messages. They originated in the United States law enforcement community before the second World War. There is no universal, official set of 10-codes, and the meanings of a particular 10-code can vary between one jurisdiction and another: a code meaning "I have the suspect in custody" in one state can mean "Send an ambulance" in a second state and have yet another meaning in a third.

The following is a sample of commonly used 10-codes, submitted for purposes of illustration. It is common for a 10-code to have numeric gaps.

10-1 Poor reception 10-2 Good reception 10-4 Message received 10-5 Relay this information to ___. 10-6 Busy 10-7 Out of service 10-8 In service 10-9 Please repeat your message 10-13 Civilians present and listening 10-15 Enroute to station with suspect 10-19 Return to station 10-20 Specify location/My location is ___. 10-21 Place a phone call to ___. 10-22 Disregard 10-23 Stand by on this frequency 10-33 Emergency traffic follows. Hold routine messages. 10-34 Frequency open (cancels 10-33) 10-39 False alarm, premises was occupied 10-40 False alarm, no activity, premises appears secure 10-41 Begin watch 10-42 End watch 10-45 Fueling vehicle 10-49 Enroute to assignment 10-60 Specify time complainant called 10-97 Arrival at assignment location 10-98 Departing assignment location