Social media marketing has become one of the most influential marketing tools in the digital business environment. Platforms such as Instagram, Facebook, YouTube, LinkedIn, and Twitter/X have transformed the way businesses communicate with consumers and influence their purchase decisions. This study examines the impact of social media marketing on consumer buying behaviour by analyzing influencer marketing, online reviews, social media advertisements, and user-generated content. The study adopted a descriptive research design using both primary and secondary data. Primary data were collected from 150 respondents using structured questionnaires. Statistical tools such as percentage analysis, chi-square analysis, and correlation analysis were used for interpretation. The findings reveal that Instagram and YouTube are the most influential platforms affecting consumer buying decisions. Influencer recommendations and online reviews strongly impact customer trust and purchase intention. Correlation analysis revealed a strong positive relationship between social media marketing and consumer buying behaviour (r = 0.87). The study concludes that social media marketing has become a strategic necessity for organizations seeking long-term business growth and customer engagement.