Antimicrobial resistance (AMR) is a global public health problem affecting healthcare systems. Short-term antibiotic non-adherence is thought to be one of the factors contributing to antibiotic resistance. This study aimed to evaluate knowledge and practices towards short-term antibiotic use on self-reported adherence among patients visiting level-1 hospitals in Lusaka, Zambia. This was a multicentre institutional-based cross-sectional study conducted among 385 adult participants from 11 September to 30 September 2023 using an adopted structured questionnaire. Analysis of the data involved descriptive and inferential statistics, where significance was determined at P < 0.05. Of the 335 participants, 56.7% displayed good knowledge and 77.3% low adherence towards antibiotic use. 54.6% thought that antibiotics were effective for viral infections, and 43.9% correctly recognized the definition of AMR. Being in formal employment (crude OR: 2.5, CI: 1.08-5.78, P: 0.032) was significantly associated with a higher likelihood of good knowledge about antibiotics while being divorced (adjusted OR: 2.5, CI: 1.23-6.10, P: 0.013) and having good knowledge (adjusted OR: 2.9, CI: 1.73-5.10, P = 0.048) were significantly associated with a higher likelihood of adherence to antibiotics. Regarding antibiotic practices, half (50. 0%) of the respondents had utilized antibiotics in the previous year while 58.2% had taken antibiotics for addressing a common cold. Furthermore, 74% reported to have bought antibiotics without a prescription. This study found that participants attending level-1 hospitals had relatively good knowledge and poor adherence towards antibiotic use. Additionally, the participants demonstrated poor antibiotic use practices in almost all statements related to antibiotic usage.