Systems and methods for transferring data over a voice channel during a voice communication connection (e.g., a telephone call) using DTMF signals over a single voice communication channel. The arbitrary data can include contact information, graphics, photographs, streaming media, interactive game information, location information, cached web pages, audio clips, etc. Some or all of the standard DTMF signals can be uniquely mapped to groups of bits. For example, the standard DTMF signals for numbers “0” through “7” can be mapped to the corresponding three-bit binary representations of those numbers. The arbitrary data can be placed in a container with meta-data indicating the start and end of the data, the type of the data, the amount of data, error correction/detection information, etc. The receiver can prevent the DTMF signals from being converted to audio signals to spare any human listeners from hearing the DTMF signals.