Swimming is an integral part of sport at Monmouth School for Girls and is popular amongst all year groups.

Pupils have access to swimming as part of their PE lessons in years 7 and 8 and as an extra-curricular activity for all year groups. All extra-curricular swimming takes place with Monmouth School for Boys and pupils are able to access Swimming Club, which focuses on swimming for fitness, lifesaving and personal survival as well as basic competitive swimming skills. The Swimming Squad allows pupils to develop their competitive skills further and access a number of high-quality training sessions.

Water polo takes place at Monmouth School for Boys and enables pupils to engage in a mixture of ball skills and fitness training.