How to Build a Subscription Billing System in India (2026): Mandates, Proration, Dunning, GST Invoices, and Build vs Buy

Short summary

A comprehensive guide to building subscription billing systems in India, covering RBI e-mandate rules, UPI Autopay's Rs 15,000 AFA-free threshold, proration math, dunning workflows, and GST-compliant invoicing. Written from production experience across three real products. Includes an honest build-vs-buy analysis for teams outgrowing raw payment gateway integrations.

• •India's recurring billing requires mandate registration (UPI Autopay, e-NACH) with specific per-debit limits and RBI rules
• •Covers the full billing lifecycle: plans, proration, dunning, GST invoices, self-serve portal, and revenue analytics
• •Written from production systems at PlugEV, CloudNX, and MultiVendor CRM with build-vs-buy guidance

Generated with AI, which can make mistakes.