The Unified Health System (UHS) aims to ensure health as a citizen's right and a State duty through a regionalized and hierarchical network of actions and services. Health Information Systems (HIS) support decision-making and the management of health organizations through information management. In 2013, the Ministry of Health launched the e-SUS Primary Care (e-SUS PC) strategy to digitize Primary Health Care, including technological infrastructure such as computers, broadband internet access, and mobile devices for data registration. This work aims to quantify how many computers in conditions of use there are in the basic units in the municipality of São Luís, how many of these units have internet, how many devices have internet access in the unit and how many units use paper forms and electronic handbook. The data was extracted from the Health Minister website in the section “National Program for Improvement of Access and Quality (NPIAQ) and transversally analysed. The municipality of São Luís has 63 registered UBS, of which 76,2% participated in the 3rd cycle of NPIAQ, revealing variations in technological infrastructure. Of the 125 recorded devices, only 51,2% have internet access, and 25% UBS lack any connection, hindering the use of systems such as the Electronic Patient Record (EPR), adopted by only one unit. Although 97% of BHU in Brazil are digitized, the total number of computers does not match the number of connected devices, and only 69,4% units with internet operate continuously. The quality and availability of the connection directly affect the efficiency and working conditions in the BHU, highlighting the need for greater digital integration. The informatization of BHU in São Luís is progressing, but challenges remain, particularly in connectivity and the use of systems like the EPR, which is available in only one unit. The discrepancy between the number of devices and those connected to the internet undermines the efficiency of activities. Improving connection quality is essential to integrate and optimize healthcare services.