The high altar, the communion rail and the side altars of the Crypt of the Basilica de los Sacramentinos were commissioned to the “Marbrerie Guiraud Fres” workshop in Toulouse, France in 1913 and are made of marble, standing out among them the High Altar due to its exquisite decor. The altars were brought in sections and arrived in Santiago in 1922. They were assembled by the famous Marmolería Ceppi.

The keynote of left lateral altar is the image of the Virgin of Carmel and the right lateral altar, by the images of Saint Joachim and Saint Anne.

The pulpit carved with images of the Apostles, the choir stalls, the benches and the confessionals were made in the workshops of the Salesian Fathers.

The lateral chapels, where the confessionals are located, are very dimly lit by the windows of the vitreaux, all made in Chile and with different religious motifs.

Above the columns of the lateral naves are carvings of the Stations of the Cross.

The access stairs are of marble with bronze handrails. At the entrance, there is a great image of Christ on the Cross.

In the Upper Temple, the lateral chapels of the naves accommodate the devotional altars and confessionals. Their ceiling is vaulted and they are furnished with semicircular arched windows and vitreaux made in Chile with different religious motifs.

Most prominent among them is the devotional altar with the image of Saint Peter Julian Eymard, made in Rome. Also worthy of mention is the image of the Immaculate Conception, the Virgin of Carmel and the marble work of the image and the altar of Our Lady of the Blessed Sacrament.

The High Altar dedicated to the perpetual exhibition of the Blessed Sacrament is made in marble and was ordered from the workshops of the Artista Magna in Argentina, along with the altar of Our Lady of the Blessed Sacrament.
At the center of the High Altar stands the shrine that exhibits the Blessed Sacrament, a large piece of bronze brought from France and watched over by two angels.

The apse of the gallery is decorated with semicircular stained glass windows, all made in Chile.

Continuing through the gallery but in the transept sector, there are six large stained glass windows made in France. The motifs of these stained glass windows are related to the history of the construction of the temple and have suffered some damages. Different female and male characters who helped in the construction of the temple can be seen, particularly the one that portrays Archbishop Crescente Errázuriz with the maquette of The Sacramentinos in his hands and the one that portrays architect Ricardo Larraín and engineer Victor Auclair.

Towards the choir is the organ built by the Walcker House and brought from Germany.

The bronze doors were carved by Chilean metalsmiths.