This study investigates the impact of financial inclusion on economic growth in Nigeria, a country where a significant portion of the population remains financially excluded despite ongoing efforts to enhance access to financial services. The problem addressed is the limited understanding of how various aspects of financial inclusion, particularly mobile money, banking services, and credit availability, affect Nigeria's GDP growth. The primary objectives of the study are to assess the current level of financial inclusion, analyze its relationship with GDP growth, and provide evidence-based policy recommendations to improve financial access and support economic development. To achieve these objectives, a secondary data analysis was conducted, employing multiple linear regression, Pearson correlation, and Granger causality tests. The findings reveal a marginally significant positive relationship between Mobile Money Subscriptions (MMS) and GDP growth, while access to formal banking services and credit availability showed no significant correlation with economic growth. These results highlight the importance of mobile money as a key driver of financial inclusion, contrasting with the limited impact of traditional banking services. Based on these findings, the study recommends enhancing mobile money infrastructure, strengthening financial literacy programs, promoting inclusive banking models, and fostering collaboration with fintech firms. Implementing these recommendations could significantly improve financial inclusion in Nigeria, ultimately contributing to sustained economic growth and enhanced welfare for the population.