This study investigated the influence of marketing infrastructure and digital marketing strategies on the performance of small and medium enterprises (SMEs) in Nigeria, emphasizing the mediating role of digital transformation. While prior research has established the importance of digital marketing strategies in driving performance, much of the focus has been on large firms, with limited attention to SMEs and the transformative effects of digital transformation. To address this gap, data were collected from 400 SME managers and owners registered with the Small and Medium Enterprises Development Agency of Nigeria (SMEDAN) through an online survey. The data were analyzed using partial least squares structural equation modelling (PLS-SEM). Findings revealed that marketing infrastructure and digital marketing strategies do not directly improve marketing performance; rather, digital transformation serves as a critical mediator that enables this relationship. The study concludes that SMEs that embrace digital transformation, by integrating digital technologies across operations, achieve superior marketing outcomes, including enhanced brand awareness, customer acquisition, conversion rates, and customer satisfaction, ultimately leading to higher sales, profitability and and business sustainability.