Canadian Common Short Codes can be five or six digits long.
Common Short Codes beginning with a leading '4' are reserved for private use by wireless network operators. Four-digit Common Short Codes are not permitted due to handset incompatibilities. Short code-based messages vary between zero-rated (paid for by campaign), standard rate (user is responsible for standard carrier charges), and premium rate (varies, C$1-10). Canadian Short codes are governed by the Canadian Wireless Telecommunications Association.