<p>This paper investigates the impact of internal factors, such as information technology readiness and owner/manager commitment, and external factors, such as regulatory support and competitive pressure, on the use of accounting information systems (AIS) levels among Iraqi small and medium-sized enterprises (SMEs). A quantitative approach via self-administered questionnaires; 190 self-administered questionnaires were distributed to the managers and owners of SMEs in Basra using a purposive sampling technique and analyzed using the partial least squares structural equation modeling (PLS-SEM) approach. The findings of this study demonstrated that internal factors, including information technology readiness and owner/manager commitment, and external factors, including regulatory support and competitive pressure, significantly and positively influenced SMEs’ AIS usage levels. The study provides meaningful contributions by expanding understanding of the use of AIS in controlling processes, operational efficiency, planning processes, and financial reporting, which assist SME managers and owners in sound decision-making and in creating short- and long-term strategies to survive in a competitive market, with a focus on both internal and external factors. The study recommended that the managers and owners could focus on multiple levels of AIS use when developing system processes.</p>