This study examines the adoption of mobile banking services among youth in Nairobi slums, focusing on their financial inclusion and economic outcomes. Data was collected through a structured survey administered by trained interviewers, focusing on 500 participants aged between 18 to 35 years. Mobile banking adoption rates varied significantly across age groups. Younger adults (aged 18-24) showed higher adoption at 67%, while older adults (aged 25-35) had a lower rate of 43%. Analysis also revealed that mobile banking users experienced an average income growth of $100 per month. The study concludes that mobile banking has potential as a tool for financial inclusion among youth in Nairobi slums, though adoption rates vary by age and socio-economic status. Future research should focus on improving access to digital technologies in these communities to maximise the benefits of mobile banking services. Model estimation used $\hat{\theta}=argmin_{\theta}\sum_i\ell(y_i,f_\theta(x_i))+\lambda\lVert\theta\rVert_2^2$, with performance evaluated using out-of-sample error.