Located in the Ciutat Vella district, the building of the Mercantile Credit Society stands on the southern corner of the block bounded by Carrer Ample, Carrer dels Còdols, Carrer de la Rosa and Carrer de Serra. It has two facing façades onto the first two streets and shares a partition with the neighbouring plot. The principal entrance is from Carrer Ample. Rectangular in plan, the building’s vertical structure comprises a semi-basement, ground floor, two upper floors, an attic and a roof terrace, although the attic is not visible from the façade facing Plaça de la Mercè. The main entrance leads into a vestibule area and to a central rectangular courtyard from which rises the principal staircase providing access to the main (first) floor. The two façades organise their openings along vertical axes in a regular rhythm: shutters and large windows on the ground floor, enclosed balconies on the principal floor, and windows on the second floor and in the attic. Both façades, profusely ornamented, are entirely finished in Montjuïc stone. The semi-basement forms part of a stone plinth with a smooth finish, the same treatment used on the walls of the first and second floors and the attic. By contrast, the ground floor, as well as the pilasters framing the two façades of the building, display a finish of rusticated ashlar masonry laid in broken courses. The ground-floor windows are crowned with flat arches, except for the large entrance portal, which is topped by a segmental arch whose keystone is carved with a lion’s head holding a door knocker. In the spandrels of this arch are sculpted two large corbels composed of foliage volutes and female busts that support the large stone slab of the projecting central balcony. This balcony, enclosed by a cast-iron balustrade, features a doorway with moulded jambs and is crowned by a semicircular pediment above a frieze carved with vegetal motifs and two volute-shaped corbels. The remaining balconies on this floor share similar characteristics, although they do not project; instead, they have flush balustrades decorated with carved peltas (Greek shields) and laurel wreaths. Moreover, the pediments above their lintels are triangular. These highly elaborate decorative elements disappear in the windows of the second floor and the side façade, which are framed by a simple moulding with convex angles. The central balcony of the principal façade is flanked by two Corinthian pilasters that bear the weight of a large semicircular arch. Within this arch opens a French window flanked by two reliefs representing allegories of Industry (on the left) and Commerce (on the right). Crowning the central bay, a moulded triangular pediment rests upon the substantial cornice that finishes the façades of the building. The main doorway gives access to a rectangular vestibule with chamfered corners, which houses the staircase leading to the central courtyard, a rectangular space adorned with columns.