Threat Signal was formed in late 2003 by cousins Jon and Rich Howard, eventually they added guitarist Kyle McKnight and began writing material. In early 2004, drummer Adam Matthews joined the band. Threat Signal posted their song "Rational Eyes" on an international metal chart on GarageBand.com. After a few weeks, the song reached #1, and it has received many awards including best guitars, best drums, best male vocals, best production, song of the week, and song of the day. In August 2004 Eric Papky, Kyle's former guitar teacher, joined the band on bass. Success on GarageBand.com sparked some early record label interest and helped create a large following even prior to the band ever having played live. In August 2005 Marco Bresette replaced Eric Papky on bass guitar.

The band travelled to Los Angeles, to record with Christian Olde Wolbers of Fear Factory in September, 2005. In November of 2005, the band announced they had signed a recording deal with Nuclear Blast records. In early 2006 Adam Matthews left the band, and he was replaced by George Parfitt. In July the band took part in the Earthshaker Fest, alongside notable acts as Scar Symmetry, Communic, and Arch Enemy. On August 1, 2006, the band announced that guitarist Rich Howard had left the band to pursue other personal goals, and he was replaced by the band's bassist, Marco Bressette. This left the bass guitar duties vacant, and in late September Pat Kavanagh was announced as the new bassist. In October, the band began a North American trek with Soilwork, Mnemic and Darkest Hour. The tour ended in November, but the band announced a headlining tour of North America in early 2007 as well.

In March 2007, Threat Signal began demoing new material, but was hampered by another departure, this time Marco Bressette's. The band announced a search for a new guitarist the same day. Threat Signal was tapped as the opener for the Tour and Loathing tour alongside Protest the Hero, All That Remains, Blessthefall, and The Holly Springs Disaster.

The band have recently added a new demo song entitled "Beyond Recognition" onto their myspace page and it is believed to be set as a song for the band's second studio album.