The global marketing automation market, valued at $2,745.6 million in 2021, is projected to increase to $4,697.1 million by 2028, prompting businesses to seek effective tools to streamline their marketing processes. Open-source marketing automation software, which is often free and customizable, offers companies greater control over their data and integration capabilities across various apps and channels. The article explores ten prominent open-source marketing automation tools, each designed for specific purposes such as data analytics, email automation, and content management systems (CMS). Tools like Matomo, Mautic, Ghost, and Strapi are highlighted for their unique features, ranging from data ownership and customizable dashboards to developer-centric communities and comprehensive campaign management. Additionally, it discusses how n8n, a free workflow automation tool, can seamlessly connect these open-source tools with existing tech stacks to enhance efficiency and user engagement.