It has a roll of approximately 450 girls with around one third of the school being boarders from both around New Zealand and overseas.

The school is named after Saint Hilda, a 7th-century English abbess remembered for the influential role she played in the Synod of Whitby.

Occupying a site bounded by Cobden Street, Heriot Row and Royal Terrace, the original buildings have been demolished and the site redeveloped from the mid 20th century.

As a state-integrated school, Saint Hilda's Collegiate School charges New Zealand-resident students compulsory attendance dues plus requests voluntary donations.

[1] As of 2024, the school has an Equity Index of 386,[3] placing it amongst schools whose students have fewest socioeconomic barriers to achievement (roughly equivalent to deciles 9 and 10 under the former socio-economic decile system).