The present study covers a pattern of commercial institutions in Boulaq, Cairo, namely Iskandar Pasha Wikala based on the Endowment Document dated 24 Ramadan 965 AH/1558AD till the completion of building on 15 Rajab 966 AH/1559AD. The location of the wikala has been defined on Souk El-Hatab St. Its four boundaries, the origin of the land ownership, and the buildings that occupied the place when Iskandar Pasha bought it were defined, as well. Most of these buildings did the same commercial business due to the nature of the location in one of the most river commercial ports in Egypt. The Endowment Document showed that the wikala consisted of two floors. The ground floor contained collecting areas, shops, and a grain barn, whereas the upper floor contained resident and collecting areas. Moreover, the wikala had one façade, i.e., the north façade. Stones, baked bricks, gypsum, and wood were used in building the wikala. The study concluded a proposal of the architecture of the Wikala of two floors for trade and residence. Furthermore, the wikala was planned according to the traditional architectural pattern of wikalas in the Mamluk and Ottoman eras.