Subscription Management & Recurring Billing platforms manage the operational lifecycle of subscription-based revenue — plan catalog management, subscriber provisioning, billing cycle automation, proration, usage metering, dunning, and renewal/upgrade/downgrade workflows. Core capabilities include flexible plan and pricing configuration, automated invoice generation on recurring schedules, usage-based and hybrid billing models, payment retry and dunning logic, subscriber self-service portals, and integration with payment gateways, CRM, and revenue recognition systems. The category spans enterprise billing platforms (Zuora Billing, Chargebee, Recurly, Stripe Billing) and vertical-specific tools for SaaS, media, and telecom.