A major redecorating project took place from 1902 to 1904 when the Gothic arched ceilings, six side-aisle windows and electric lights were added.

Pope John Paul II established the Diocese of Colorado Springs on November 10, 1983.

[5] The 1916 Hinners pipe organ was replaced in 2002 and another major renovation of St. Mary's was completed in 2003.

The interior was renewed and a new entrance was built on the southwest corner of the church, a gathering space, plaza and meeting rooms were added.

The ruins of St. Mary's Cathedral appear in the post-apocalyptic video game Horizon: Zero Dawn.