This article examines the report as a new type of document in the business writing system of the first half of the 18th century. The aim is to identify common and distinctive features of reports from various institutions in the southern region of Russia. The materials used for this study are documents from the Don Army (State Archive of the Volgograd Region) and the Astrakhan Province (National Archive of the Republic of Kalmykia). Through a comparative analysis of their content, functions, and speech organization, it is revealed that all reports were submitted from subordinate subjects to superiors, served informative purposes, and occasionally served as accompanying documents. They shared a similar form (addressee, addresser, title, main text, date, place of creation), although there were variations in the placement of requisites, document titles, and addresser formulas. Differences were also identified, such as the larger number of reports in the documentation of the Don Army and their frequent use as accompanying documents, while Astrakhan reports often contained financial reports. In Don reports, the addresser was referred to in the final formula as “about this report,” while Astrakhan reports only included their name (or signature). It can be concluded that reports were increasingly integrated into official communication, becoming firmly established in the military sphere, and their form became more standardized, reflecting the development of common rules for document management.