Background: Health literacy is a relatively new concept in the South African primary healthcare (PHC) sector as well as globally, and limited new literature is available on the topic. In this study, we focused on investigating, describing and comparing health literacy scores calculated using three different tools to assess a patient’s level of English comprehension. Health literacy is defined as the degree to which patients have the capacity to obtain, process and understand basic health information and services to make appropriate health decisions. South Africa is a linguistically and culturally diverse country, yet English is often used as the main language for imparting health education in PHC facilities. Patients often do not comprehend the health education received. Primary... healthcare workers need to determine the health literacy levels of their patients before imparting health education. The REALM-R (SA 1, 2 and 3) tools are adapted from the original REALM-R to test health literacy levels of South African PHC patients. The Learning Ability Battery (LAB) is a tool used to determine English comprehension levels.Aim: The aim of this was to investigate, describe and compare health literacy and English comprehension levels of PHC patients using three locally adapted REALM-R (SA) tools and the LAB.Setting: This study was conducted at five PHC facilities in the City of Tshwane, Gauteng.Methods: A prospective, quantitative and comparative design was chosen for this study. In general, a descriptive design was applied for the presentation of the results. The sample size was 200 patients from five different PHC clinics. Data were collected using REALM-R (SA 1, 2 and 3) to determine the health literacy levels and the LAB to determine the English comprehension levels.Results: Majority of the patients scored high using the REALM-R (SA) tools. For the LAB, 68% scored 11–40 out of 50. Only 8% scored 41–50 out of 50. A significant difference was found between the actual school grade achieved and the school grade according to the LAB.Conclusion: The results of the study indicated that although patients are able to read and pronounce medical words as such used in the REALM-R (SA) tools, it does not necessarily mean that they are able to comprehend the meaning of the words as indicated by the results of the LAB. Currently, the REALM-R (SA) tools only test health literacy levels based on word recognition and pronunciation. It is recommended that a word comprehension section be added to determine patients’ understanding of the words.