Sligo Grammar School is a private fee paying co-educational boarding school located on The Mall in Sligo. The school has approximately 450 students of which approximately 100 are boarders. It offers the traditional Junior Certificate and Leaving Certificate courses along with Transition Year, which is compulsory. It is under Church of Ireland management. The school has a number of international pupils, including from Spain, Germany, South Korea, Russia and Ukraine.

Extracurricular

Sligo Grammar School were Senior Connacht Rugby Champions in 2014 for the 10th time. Their most successful senior cup campaign was in 2010 when they went the entire season unbeaten. The 2010 cup team defeated Blackrock College, Clongowes and Campbell college on their way to lifting their first senior cup in 15 years. 

The school also has an athletics association and hockey teams for girls. Competitive debating teams in English, Irish and German also exist. The school has an SATB choir with approximately 70 members.