Billing & Invoicing
Status: Planned Q2 2026
Complete billing system with invoice generation, payment tracking, and subscription management.
Overview
The Billing context will provide end-to-end billing capabilities, from invoice generation to payment processing and subscription lifecycle management.
Planned Features
Invoice Management
Invoice Generation:
- Create invoices from orders automatically
- Manual invoice creation
- Recurring invoice schedules
- Pro-forma invoices for quotes
Invoice Details:
- Line items with quantity, price, tax
- Multiple tax rates (VAT, GST, sales tax)
- Discounts and promotions
- Currency support (multi-currency)
Invoice Delivery:
- Email with PDF attachment
- Customer portal access
- Print-ready PDF format
- Electronic invoicing (e-invoicing)
Payment Tracking
Payment Methods:
- Credit/debit cards (Stripe, PayPal integration)
- Bank transfer (ACH, SEPA)
- Wire transfer
- Cryptocurrency (optional)
Payment Status:
- Pending → Paid → Overdue workflow
- Partial payments tracking
- Payment reminders (automated)
- Late fees calculation
Payment History:
- Transaction log per customer
- Payment receipts generation
- Refund processing
- Chargeback handling
Subscription Management
Subscription Plans:
- Monthly, quarterly, annual billing
- Trial periods (7/14/30 days)
- Freemium plans
- Custom pricing per customer
Lifecycle Management:
- Auto-renewal with payment retry
- Upgrade/downgrade flow
- Proration calculations
- Cancellation and pause
Subscription Analytics:
- MRR (Monthly Recurring Revenue)
- Churn rate by plan
- Upgrade/downgrade trends
- LTV (Lifetime Value) calculation
Revenue Recognition
Accounting Compliance:
- ASC 606 / IFRS 15 standards
- Deferred revenue tracking
- Revenue recognition schedules
- Accrual accounting support
Financial Reports:
- Accounts Receivable (AR) aging
- Revenue by product/service
- Tax liability reports
- Revenue forecast
Automated Reminders
Payment Reminders:
- 7 days before due date
- On due date
- 7 days overdue
- 30 days overdue (final notice)
Subscription Renewal:
- 14 days before renewal
- Failed payment notifications
- Card expiration alerts
- Dunning management (retry failed payments)
Multi-Currency Support
Currency Handling:
- 150+ currencies supported
- Real-time exchange rates
- Customer preferred currency
- Multi-currency reporting
Tax Compliance:
- VAT calculation (EU)
- GST handling (India, Australia)
- US sales tax by state
- Tax exemptions management
Technical Architecture
Billing Engine
Invoice Generation:
- Template-based PDF generation
- Customizable invoice templates
- Watermarks and branding
- Multi-language support
Payment Gateway Integration:
- Stripe Connect
- PayPal Express Checkout
- Square
- Adyen (enterprise)
Subscription Engine:
- Cron-based renewal checks
- Payment retry logic (smart dunning)
- Webhook handlers for payment events
- Idempotent operations
Data Model
Core Entities:
- Invoice (aggregate root)
- InvoiceLineItem (entity)
- Payment (aggregate root)
- Subscription (aggregate root)
- PaymentMethod (value object)
Events:
InvoiceCreatedInvoicePaidPaymentFailedSubscriptionRenewedSubscriptionCancelled
Integration Points
Order Management
Order-to-Invoice:
- Automatic invoice creation on order fulfillment
- Invoice status updates order
- Refunds trigger credit notes
Customer Management
Customer Billing:
- Billing address from customer profile
- Payment history per customer
- Credit limit enforcement
- Billing preferences
Event Bus
Domain Events:
- Payment notifications to accounting system
- Subscription events trigger onboarding
- Failed payments alert sales team
- Revenue recognition updates analytics
Use Cases
SaaS Subscription
Monthly Billing:
- Customer subscribes to Pro plan ($99/month)
- Trial period: 14 days free
- Day 14: Charge first payment automatically
- Every 30 days: Auto-renew and charge
- Failed payment: Retry 3 times over 7 days
- Still failed: Downgrade to Free plan
E-commerce Orders
Order Billing:
- Customer places order for $250
- Invoice generated automatically
- Email sent with payment link
- Customer pays via credit card
- Payment confirmed, order ships
- Receipt emailed
B2B Services
Net-30 Payment Terms:
- Service delivered monthly
- Invoice sent on 1st of next month
- Payment due: 30 days (Net-30)
- Reminder: 7 days before due
- Overdue: Late fees applied (2% per month)
- Accounting: AR aging report
Roadmap
Phase 1: Basic Invoicing (Q2 2026)
- [ ] Invoice generation (manual + auto)
- [ ] PDF export with templates
- [ ] Payment tracking (paid/pending/overdue)
- [ ] Email delivery
- [ ] Stripe integration
Phase 2: Subscriptions (Q3 2026)
- [ ] Subscription plans management
- [ ] Auto-renewal engine
- [ ] Payment retry logic
- [ ] Upgrade/downgrade flow
- [ ] Trial period handling
Phase 3: Advanced Features (Q4 2026)
- [ ] Multi-currency support
- [ ] Tax calculation engine
- [ ] Revenue recognition
- [ ] Dunning management
- [ ] PayPal, Square integrations
Why Wait for This Module?
You can start using Promenade today and add billing later:
- Manual Invoicing: Use external tools (QuickBooks, Xero)
- Payment Links: Stripe Checkout or PayPal buttons
- Spreadsheet Tracking: Export customer data to Excel
- Third-Party Integration: Use Zapier to connect
When Billing module launches (Q2 2026), you'll get:
- Native invoice generation
- Automated subscription billing
- No third-party dependencies
- Full integration with Orders and Customers
Related Documentation
- Order Management - Orders generate invoices
- Customer Management - Customer billing data
- Event-Driven Architecture - Payment events
- RBAC - Access control for billing
Questions? Open a discussion
Want this sooner? Sponsor development to prioritize Billing module.