A method and system for secure call Dual-Tone Multi-Frequency (DTMF) signaling includes entering (202) dial string of a telephone number of a destination device, assigning (210, 212) the dial string to a predefined string having a total length that is greater than the dial string such that there will be at least one leading hexadecimal bit in the predefined string length that is not used when the entered dial string is converted to a hexadecimal, converting (214) the dial string to hexadecimal, reversing the order of the hexadecimal, and placing the reversed hexadecimal at the beginning of the predefined string, appending (216) “one” bits to the predefined string length indicating how many nibbles of the predefined string length are unused, if any, and appending the remaining intervening unused bits in the predefined string length to “zero” bits, and sending (226) the encoded string length.