21 Moorfields is located in the northern part of the City of London, right above Moorgate underground station and the new Moorgate Crossrail underground station. The project is arranged as two buildings - the 80 m (262 ft) high East Building and the smaller, 3-story high West Building - connected at podium level and arranged around a green public square.

Both blocks of 21 Moorfields are predominantly clad with unitized façades, story-high, with a total of 30 main façade types (with more than 50 façade sub-types) including closed cavity façade (CCF), steel-glass façades, unitized sheet metal façades, skylights, interior façades, balustrades, concrete façades (Precast), soffit sheets (partly with glass fiber reinforced concrete panels - GRC) and approx. 80 doors of various designs. The standard façade unit sizes are 1.5 m x approx. 4 m and 3 m x approx. 4 m, while the biggest panels are approx. 3 m x 8 m. The closed cavity façade (CCF) units measure 3 m x 4 m to 5 m. On the ground floor, a façade supported by glass blades will feature glass panes and glass blades up to 11 m high.
The building will meet the BREEAM sustainability standard.