The exact qualifications are different at England & Wales, Northern Ireland and Scotland. Private prisons also have slightly different qualification criteria for their prison officers. The general qualifications are: you should be aged at least 18, should have British, EU or Commonwealth citizenship, be able to declare any convictions and pass medical, fitness and eyesight tests. There will be elaborate background checks to ascertain your identity, activities, etc. Experience in police or armed forces also can benefit.

In England, you will go through an entrance examination, where your numerical skills, language skills and etc are tested. In Scotland, you need at least five S grades including English and maths. After joining as prison officer, you will be undergoing training to achieve qualifications like SVQ Level 3 in Custodial Care. There are also Intensive Development Scheme in England and Wales, which would help you achieve promotions and seniority fast.