Browse free open source Invoice software and projects for Windows below. Use the toggles on the left to filter open source Invoice software by OS, license, language, programming language, and project status.

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  • 1
    Invoice Ninja

    Invoice Ninja

    Free and Open Source Invoicing, Expenses & Time-Tracking

    Invoice Ninja is a free and open source invoicing, expenses and time-tracking app built with Laravel and Flutter. It offers a plethora of great features, including custom branded invoice design, recurring invoicing and auto-bill clients, real-time quote creation and custom proposals, expense reporting and so much more! Invoice Ninja is also capable of handling online payments from more than 40 payment gateways, including Stripe, PayPal and WePay. It also accepts payments using credit cards, ACH, Bitcoin and more. Get paid online, organize project workflows with Kanban Boards, and track time online via your Webapp account all with Invoice Ninja.
    Downloads: 20 This Week
    Last Update:
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  • 2
    Kimai - Time Tracking Software

    Kimai - Time Tracking Software

    Time-Tracking for companies and teams with up to 250+ users

    Kimai is web based software that tracks work time, and classifies it. It tracks time and prints out a summary of your activities on demand. Yearly, monthly, daily, by customer, by project, by action. FETCH THE LATEST DOWNLOAD FROM GITHUB: https://github.com/kimai/kimai/releases Record expenses and print customizable invoices in different formats. For further information visit: - https://www.kimai.org - https://www.kimai.cloud - https://github.com/kimai/kimai
    Downloads: 5 This Week
    Last Update:
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  • 3
    TEMS -Time and Expense Management System

    TEMS -Time and Expense Management System

    Captures time & expense by project and account; generates invoice

    Keeps track of times entry and expenses reports of employees and contractors by projects and accounts, automatically generates invoices with details. You can print weekly time cards and expense reports by employee, project, and account. It allows you to review and approve times & expenses before generating invoices. This application is ideal for who bills their clients by time and material basis, such as IT consultants, Lawyers, CPAs, Government Contractors etc. Full featured demo site: http://tems.sourceforge.net Play with it from your browser to find out if it will fulfill your requirements, before downloading it.
    Downloads: 1 This Week
    Last Update:
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  • 4
    Multiplatform webbased timereporting system. Generic database support (MS SQL, MySQL...). Generate reports on employees, worked hours in projects. Automatically generate invoices based on an hourly fee (by employee). Gant charts for planning resources
    Downloads: 1 This Week
    Last Update:
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  • The All-in-One Commerce Platform for Businesses - Shopify Icon
    The All-in-One Commerce Platform for Businesses - Shopify

    Shopify offers plans for anyone that wants to sell products online and build an ecommerce store, small to mid-sized businesses as well as enterprise

    Shopify is a leading all-in-one commerce platform that enables businesses to start, build, and grow their online and physical stores. It offers tools to create customized websites, manage inventory, process payments, and sell across multiple channels including online, in-person, wholesale, and global markets. The platform includes integrated marketing tools, analytics, and customer engagement features to help merchants reach and retain customers. Shopify supports thousands of third-party apps and offers developer-friendly APIs for custom solutions. With world-class checkout technology, Shopify powers over 150 million high-intent shoppers worldwide. Its reliable, scalable infrastructure ensures fast performance and seamless operations at any business size.
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  • 5
    OnlineBilling Create and Present Invoices. Manage Teams and Contracts. Frontend for TUTOS to enable EBPP ( Eletronic Bill and Project Presentment) First version is online at http://OnlineBilling.at Manage your daily paperwork, easily create invoices.
    Downloads: 0 This Week
    Last Update:
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  • 6
    PHPBounce

    PHPBounce

    Web Application used to manage clients, create invoices, timesheets

    This web application is used to manage day to day service related businesses. PHPBounce comes with a multi tiered user system with Admin / Manager / Users, timesheet management, ticketing system, client database, invoice system, credit card processor (google checkout / google wallet). Client portal for your clients to keep track of invoices, tickets, and make payments.
    Downloads: 0 This Week
    Last Update:
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