Presented here is a catalogue of attested porticus in the city of Rome from c. 200 BCE to 400 CE. It is organised into seven headings: identification, date and location, form, function, ancient testimony, bibliography, and FUR (if it is represented on the Severan Marble Plan). It represents primary research conducted for my PhD dissertation concerning the development of porticus spaces in Rome’s built environment. This table presents those structures directly identified in our sources as porticus. Generally, the Latin term corresponds to the English ‘portico’ or ‘colonnade’, and so infers an interior space generated by a sequence of columns supporting a roof. However, the term porticus could actually refer to an exceptional variety of structures, comprised of multiple aisles, storeys or wings, and in different functional contexts, commercial, religious, etc. To be clear, porticus spaces, by their very nature, defy strict typological classification. This is because of their functional versatility and their continuing presence in a built environment which changed over time. At first, I did attempt to categorise porticus into a strict set of criteria including: ornamental, connective, sacred, garden, piazza, commercial, and more besides. However, it quickly becomes evident that porticus fit many of these, and at different times in their functional history. I chose, then, to present the entries alphabetically. I want to stress that each porticus needs to be considered in its context, historical and topographical. This research began through reference to topographical dictionaries including Platner and Ashby (1929), Richardson (1992), the LTUR (1993-2000), the Digital Augustan Rome Project (2002), Carandini et al.’s Atlante (2012), as well as the Stanford Digital Forma Urbis Romae Project (2002-2016). Such publications have made this research possible, not least in working remotely during the lockdowns of 2020 and 2021. Throughout, there is an attempt to present current scholarly debates surrounding some of these spaces as clearly and concisely as possible. This is by no means a comprehensive catalogue of porticus spaces for this time period. Still, I hope the presented material here is useful. Constructed with the purpose of promoting the importance of porticus spaces at Rome, I hope it can contribute to our developing knowledge about life in Rome’s built environment and a platform for future research. In future, I would like to incorporate my photographic archive alongside a digital map. Of course, feel free to get in touch with any queries.