The founding headmaster, Mr W J Warren, was previously the joint principal of Banbridge Academy before serving in World War I in 1914-18.

In October 1924, a house on the Edenderry bank of the River Bann was purchased by a group of prominent local citizens (for a sum of £4,400) and made available to Mr Warren to establish Portadown College.

The college has made a major contribution to the current 'two-tier' system of secondary education in the Craigavon area, known as the Dickson Plan.

The house structure provides the basis for a wide range of inter-house competitions, including sports, music and debating.

The houses are named after the following: Portadown College has been officially recognised in the field of sporting excellence and has been awarded the status of a Sportsmark School.

[5] Representative teams participate in Rugby, Boys and Girls Hockey, Netball, Football, Volleyball, Golf, Tennis, Cricket, Rowing and Athletics.

Although sport plays a key role in the school's extracurricular activities, there are a number of other societies that include: drama, debating, Duke Of Edinburgh Award expedition and charity group.

Until Late 2019, 814 (Portadown College) Squadron of NI Wing, Air Training Corps was Headquartered at the school.