Invoice Ninja: Open-Source Invoice and Payment Management Software

What is Invoice Ninja?

Invoice Ninja is a comprehensive open-source invoicing and payment management platform designed for freelancers, consultants, small businesses, and agencies. It streamlines the entire billing workflow—from creating professional invoices to accepting payments online to tracking receivables.

Instead of juggling spreadsheets, word processor templates, and manual payment tracking, Invoice Ninja provides a complete platform for managing client billing relationships. Create invoices in seconds, send them directly from the application, track payment status, and accept credit cards or bank transfers.

Invoice Ninja supports multiple currencies, languages, and payment processors, making it ideal for businesses with international clients. Every invoice is professionally designed and customizable with your branding.

Key Features

• Professional Invoice Creation: Beautiful, customizable invoice templates that reflect your brand. Send directly from the application.
• Automatic Invoice Numbering: Automatic sequence tracking and invoice numbering for compliance and organization.
• Payment Processing: Accept payments via Stripe, PayPal, Square, and 50+ payment processors integrated directly into invoices.
• Client Portal: Clients can view invoices, make payments, and download documents from their portal.
• Recurring Invoicing: Set up recurring invoices for subscriptions and retainers that generate automatically.
• Time Tracking: Integrated time tracking with automatic invoice generation from logged time.
• Expense Management: Track project expenses and add them to client invoices with markup.
• Project Management: Manage projects, tasks, and time allocation integrated with invoicing.
• Financial Reports: Detailed reports on invoices, payments, expenses, and financial performance.
• Multi-Currency Support: Work with international clients using multiple currencies with automatic exchange rates.
• Custom Branding: White-label invoices and portal with your company branding.
• Client Management: Maintain detailed client database with contact information and billing history.
• Automated Reminders: Automatically send payment reminders for overdue invoices.
• API and Integrations: Full REST API for integrations with accounting software and other business tools.

System Requirements

Cloud Version

• Web browser (Chrome, Firefox, Safari, Edge)
• Internet connection
• No installation required

Self-Hosted Requirements

• Operating System: Linux or Windows
• PHP: 7.4 or higher
• Database: MySQL 5.7+ or PostgreSQL 10+
• Web Server: Nginx or Apache
• RAM: Minimum 1GB, Recommended 2GB+
• Storage: 5GB+ for invoices and attachments
• Composer: For dependency management

Installation

Docker Installation

# Using Docker Compose
version: '3.1'
services:
  mysql:
    image: mysql:5.7
    environment:
      MYSQL_ROOT_PASSWORD: ninja
      MYSQL_DATABASE: ninja

  invoiceninja:
    image: invoiceninja/invoiceninja:latest
    ports:
      - "80:80"
    environment:
      DB_HOST: mysql
      DB_DATABASE: ninja
      DB_USERNAME: root
      DB_PASSWORD: ninja

# Start services
docker-compose up -d

# Access at http://localhost
# Default: admin@invoiceninja.com / password

Cloud Version

# Visit https://www.invoiceninja.com/
# Create free account
# Start invoicing immediately
# No setup required

Use Cases

Freelancers and Consultants

Independent professionals use Invoice Ninja to manage client billing, track payments, and maintain financial records for tax purposes.

Creative Agencies

Agencies bill multiple clients for design, development, and marketing services with professional invoices and payment tracking.

Service Businesses

Plumbers, electricians, contractors, and other service providers invoice clients and accept payments on mobile devices at job sites.

Software as a Service (SaaS)

Recurring billing and subscription management for SaaS companies with automatic invoice and renewal management.

Remote Teams

Distributed teams and agencies manage invoicing and payments across time zones and currencies.

Advantages

• Zero Licensing Costs: Free and open-source eliminates monthly invoicing software subscriptions.
• Professional Appearance: Beautiful invoices reflect positively on your business.
• Payment Automation: Accept payments automatically, reducing collection time.
• Complete Financial Visibility: Track all invoices, payments, and expenses in one place.
• International Support: Multi-currency and multi-language for global operations.
• Customization: Full control over invoice appearance and branding.
• Self-Hosted Option: Keep sensitive financial data on your servers.
• Recurring Billing: Automate subscription and retainer invoicing.
• Mobile Friendly: Create and manage invoices from any device.

Limitations

• Not Full Accounting: Invoice management focused, not a complete accounting system like QuickBooks.
• Setup for Self-Hosted: Self-hosted version requires some technical knowledge to install.
• Integration Limitations: Not as many integrations as some commercial platforms.

Pricing

Software Cost: Free and open-source (Elastic License)

Cloud Hosting: Free tier available, paid plans from $10-20/month

Self-Hosted: Only infrastructure costs (server maintenance)