European businesses are increasingly shifting toward complex usage-based pricing models, driven by the need for flexible payment structures that align with actual consumption, particularly in the B2B SaaS sector. This transition is fueled by customer demand, economic pressures, and the requirement to comply with Europe's intricate regulatory landscape, including VAT variation and GDPR compliance. Lago, an open-source billing and metering solution, addresses these challenges by offering a flexible platform that supports real-time usage tracking, hybrid pricing models, and comprehensive integration with existing business systems. European companies, from AI startups to IoT service providers, have successfully implemented Lago to handle complex billing needs, enhance customer retention, and optimize revenue. By providing transparency, customization options, and robust infrastructure, Lago empowers businesses to scale their operations and maintain control over their financial data in compliance with European regulations.