Demo Users: Admin: [email protected] / admin1234 User: [email protected] / demo1234

BillFlow is a complete invoicing and billing management system built with pure PHP 8. Manage clients, invoices, quotes, expenses, and recurring billing — all from one clean dashboard. Includes a client-facing portal so your customers can view and pay invoices online.

Why BillFlow?

Unlike bloated frameworks, BillFlow runs on pure PHP 8 with no Composer dependencies. Drop it on any shared hosting and it just works. Comes with a built-in web installer — no manual database setup required.

Key Modules

• Invoices — Create, send, and track professional invoices with PDF export
• Quotes — Send quotes and convert them to invoices in one click
• Expenses — Track your business expenses by category
• Recurring Billing — Automate repeat invoices on custom schedules
• Client Portal — Clients can log in, view invoices, and pay online
• Products & Services — Reusable product/service catalog for faster invoicing
• Reports — Revenue, expense, and payment reports
• Stripe Payments — Accept online payments directly on invoices
• PDF Export — Download and send branded PDF invoices and quotes
• Multi-Language — English, Turkish, German, French, Spanish included

Technical Highlights

• Pure PHP 8.1+ — zero framework, zero Composer
• MySQL database with clean schema
• Web installer included — setup in under 2 minutes
• Tailwind CSS + Alpine.js for modern UI
• Fully responsive design
• Clean MVC architecture — easy to customize

• Invoice management with PDF export and status tracking
• Quote management with one-click invoice conversion
• Expense tracking with category management
• Recurring invoices with automatic scheduling
• Client portal — clients can view & pay invoices online
• Stripe payment gateway integration
• Product & service catalog
• Revenue and expense reports
• Multi-language support (EN, TR, DE, FR, ES)
• Web installer — 2-minute setup
• Pure PHP 8.1+ — no framework required
• Fully responsive, mobile-friendly UI
• Branding/logo customization
• Clean MVC codebase — easy to extend

• PHP 8.1 or higher
• MySQL 5.7 or higher (MySQL 8.x recommended)
• Apache or Nginx web server
• mod_rewrite enabled (Apache)
• PDO and PDO_MySQL PHP extensions
• Stripe account (optional — for online payments)

1. Upload all files to your web server or hosting
2. Create a MySQL database
3. Visit yourdomain.com/install in your browser
4. Follow the web installer steps (database, admin account setup)
5. Log in with your admin credentials and start billing

Full documentation is included in the /documentation folder.