The Marching Band at Port Isabel Early College High School is one of the largest student organization on campus with roughly 120 students involved. The Marching Band consists of students from all concert bands. Marching Band begins with a mini-camp in May, followed by summer band during the month of July, which all participants are require to attend. Once school starts, the Marching Band rehearses three times a week and performs during halftime of all football games. The Marching Band competes in various competitions on Saturdays during the fall, including (but not limited to) the University Interscholastic League (UIL) and it's advancing stages.