Objective: To evaluate implementation of the FIGO Nutrition Checklist in a low/middle‐income South African setting. Methods: This is a mixed‐methods study. Following administration of the FIGO Nutrition Checklist by a dietitian between July 2021 and May 2022, quantitative responses from pregnant (n = 96) and nonpregnant (n = 291) participants with overweight or obesity were analyzed, using logistic regression. Qualitative data from in‐depth interviews with the dietitian and a subgroup of participants (n = 15) were analyzed using reflexive thematic analysis. Results: Of 387 participants, 97.4% (n = 377) answered 'no' to at least one diet quality question on the FIGO Nutrition Checklist, indicative of an at‐risk dietary practice. Food insecurity was positively associated with having more than three at‐risk practices (OR 1.87; 95% CI, 1.10–3.18; P = 0.021). Themes from the dietitian interview included ease of use of the checklist; required adaptations to it, including explanation and translation; and benefits of the tool. Despite challenges to healthy nutrition, participant interviews identified that the checklist is acceptable and supported improved awareness of dietary intakes. Conclusion: Considering the high incidence of at‐risk dietary practices identified by the FIGO Nutrition Checklist in this population, further research into use of the tool across South African healthcare settings is warranted. Synopsis: The FIGO Nutrition Checklist was found to be acceptable, beneficial, and easy to implement within a dietary counselling session in South Africa. [ABSTRACT FROM AUTHOR]