Are you are freelancer or a proprietor of a small to medium sized enterprise? If so, then you must be putting up a lot of work into your business. Every hour spent on your hard work counts and no part of a job is so small to go uncompensated. However, getting paid means you have to send your client an invoice. And, that means you need super free open source billing software.

Why do you need invoicing software?

I’m sure you are questioning the rationale behind this invoicing software at the back of your mind. Well, to make things a bit clearer, you need to whip up something that has a professional appeal. You can prepare a simple document with your word processor or a spreadsheet. But, you need an application that can keep track of your payment and reminds you to follow up on the invoices you have already sent which can be provided by the invoice and billing software.

So, hope that you understood the importance of invoicing software

1. InvoicePlaneInvoicePlane

InvoicePlane is a self-hosted completely free invoicing software for use application for managing your invoices, quotes, clients and payments. Open source invoicing software and was built with an intention to offer free application for billing, invoicing, client management and payment tracking.  So far the application has garnered over 12,000 users in over 150 countries. Download open source invoice software for windows and Linux operating software.


  • Easily customizable to make sure it fits all your needs
  • Multi language Interface with 23+ languages
  • Easy create an invoice with one simple click
  • CRM-like customer management making it easy for you to manage your customers.
  • Easily prepare and send quote for customers with a single click.
  • Makes it easy to keep track of payments
  • Integrates well with Paypal

2. Simple InvoicesSimpleInvoices

Simple Invoices is a free open source invoicing system that supports recurring generation of sales reports, recurring payments, multiple customers and a variety of payment types. Install it yourself in case you need to use it or seek help from service providers supported by the developers. You can use the software to send invoices, track your finances and bill your clients. Download free invoicing software for Linux, windows and IOS.


  • Export to various file formats: PDF, Ms Word, Excel or just plain text
  • Can create multiple invoice types: Itemized invoices and total invoices.
  • Offers various invoice templates to choose from
  • PayPal integration for prompt payment
  • Recurring billing
  • Invoice templates – Be able to select(or create) different layouts for your invoices
  • Unlimited invoicing
  • Efficient payment tracking
  • Can be used in various languages.

3. F-BillingF-Billing

F-billing is free billing software for service providers, businesses (small and medium sized) and freelancers.  Besides, it has excellent expense tracking and cloud back up.  The software enjoys a simple user-interface and is easy to create invoices. Moreover, the software supports multiple users. Download free billing software for small and medium sized business.


  • Strong, secure yet editable products, services, and customers database.
  • Let’s you easily manage your reports and invoices and print sales commends or messages on all the reports.
  • Supports use of different currency symbols in different companies or different geographical locations.
  • Manage your invoices and reports. Print sales messages or comments on all invoices
  • Built-in software updater making sure you always have the most current and secure application.
  • Support PDF meaning you can email your reports or invoices in PDF support.

4. Sleek BillSleekBill

Sleek Bill is top free invoice software offering top invoicing features that makes it the ideal billing tool for freelancers and small businesses. The software is designed to offer the best possible user experience. Besides, it lets you create customized invoices and other necessary documents in formats of your choice – Excel or PDFs. Billing has three plans: free plan allowing a maximum of 5 invoices per month,  a single computer license at $25(with unlimited invoices) and a pro version giving you multiple computers license at $35.


  • Easily create and send estimates to your clients for review.
  • Easily add or edit client details from the database.
  • Automatically backs up your data to a local file where you can easily retrieve it just in case you need it. .
  • Allows feature to append your brand, logo and any particulars you need, to your invoice.
  • The software embeds pre-loaded data for tax (you can customize it to suit your state or country.)
  • Can be used by multiple companies
  • Paypal integration allows prompt payments.
  • Offers smart reporting

5. Invoice ExpertInvoiceExpert

Invoice Expert is your free and open source invoicing software package for your business. The software lets you send billing estimates to your client for your approval. The software is easy to use, and is usable within 5 minutes of installing. Invoice Expert free invoicing software helps organizations reduce the amount of time spent on administrative tasks as well as reduce overall invoice processing time.  The Lite Edition is free to use while the Advanced Edition goes for one time fee of $69.95.


  • Everything comes in unlimited tag: unlimited payments, invoices, products and customers.
  • The app lets you get paid faster; thanks to the seamless PayPal integration.
  • Allows you to easily export data to PDF or Excel or import existing data from Excel; thanks to its in-built data import wizard.
  • Easily customizable meaning you can append your Branding or Logo; gives a professional impression to your clients.
  • Always compatible with the latest operating system
  • Gives you detailed reports regarding your earning or expenditure.
  • Stable and secure cloud-based data backup.
  • You can send SMS notification to your client’s when the work is done and invoices are ready for payment.

6. HiveageHiveage

Hiveage is a web-hosted or locally installed open source billing software. The software is tailored small businesses and independent contractors. You can set user privileges/ roles ranging from staff, owner, contractor or admin. Moreover, the app is easy to navigate, to setup and highly intuitive. The software offers a free 30-day trial  without any limitations to the features offered. After 30 days of your free trial are over, you can choose any of the four plans. Free plan, allowing only one use and unlimited invoicing, roll your own plan at $1.95/month, Mid plan at $29.95/month and $49.95/month for the Big plan. Their customer support is over the top: email, social media, and online help center or through their blog.


  • Intuitive dashboard which provides a graph showing income/month, year-to-date invoicing and expenses summaries
  • Effortless invoicing; thanks to various attractive invoicing features.
  • Easily keep track of your bills.
  • Allows to maintain a contact lists of clients
  • Allows invoicing in different currencies.
  • Excellent import and export capabilities.
  • Effortless integration with Paypal and other add-ons.
  • Secure; thanks to SSL encryption.

7. InvoiceableInvoiceable

Invoiceable is a web-hosted (cloud-based), free and open source invoicing software solution ideal for providing free and easy-to-use tools for billing and invoicing your client.  Download free billing software compatible with any operating system – Mac, Linux or Windows. Though the software doesn’t offer a paid subscription, but you can pay a one-time fee for specific features. Otherwise, the software is free for use by anyone without any limitations. However, in order to remove inviolable branding, you have to pay a small fee of $49. Invoiceable is completely free. It has two premium features, each available for a one-time payment.


  • Easy to setup and use
  • Easy invoicing send over email
  • Allows recurrent billing
  • Can create client statement and awesome reports
  • A clean dashboard which gives good view of your invoicing, total revenue collected notification or your most active clients.
  • Supports multi-currency billing and invoicing.
  • Hassle free import and export capabilities.
  • Seamless integrations with add-ons or Paypal.
  • Secure to use
  • Excellent customer support

Never let any single minute of your hard work go uncompensated.  Or, waste hours on end of productive time creating an invoice. Learn the art of intelligent delegation. And, in this case, invoicing software can help you a great deal.