The Top 7 Open Source Invoicing And Billing Solutions in 2024

By James LePage
 on October 4, 2021
Last modified on January 7th, 2022

The Top 7 Open Source Invoicing And Billing Solutions in 2024

By James LePage
 on October 4, 2021
Last modified on January 7th, 2022

Are you looking for an open source invoicing system? We've put together this blog post for people like you. We know that in any business environment, it's impossible to generate revenue without invoicing customers. And for that, you need an open-source invoicing solution. It will enable you to bill customers effectively.

Close-up Of A Businesswoman Looking At Invoice On Computer At Workplace

In this blog, we review some of the best open source solutions that can make invoicing your clients pretty easy. We know that using Excel spreadsheets and Word documents to create invoices can cause a lot of unnecessary frustrations. We want you to replace them with an open source billing tool. All you have to do is compare features, and pick a software that suits your business. 

Before we dive in, first things first:

What is an open-source Invoicing solution? 

Open source is any system that makes its source code public for any individual or business to inspect, modify, and enhance. You may ask, "what is source code?" Source code is the element of software  developers manipulate to configure a piece of software to meet business demands. 

They can use it to add features, fix bugs, and ensure that what you get is the best piece of software. But not all source codes are the same, and some allow programmers to modify only certain software parts. 

Why does open source invoicing matter?

Using an open-source invoicing system is at the crux of growing every business venture. One of the major benefits of using it today is that it costs nothing. Who doesn't want a system like that? Plus, most open source systems work better than proprietary software anyway.

How your invoice should look like?

Your invoice should tell the client which goods or services you have provided and how much they should pay you. Now that we are clear on how an invoice should look, you need to think about an open-source system that you can use. You need to decide what features that invoicing system should have. And more.

Today open source is so widely used by many businesses. If you also use it, you're likely to reap one of the following benefits. 

1. You will use a secure invoicing system

Yep! Most open-source software offers you an extra layer of security because they are accessible to the public. Everyone gets an opportunity to review code for accuracy, bugs, and hacks. This way, many pairs of eyes can pick up any coding errors. 

In contrast, it may take days or even weeks for programmers of proprietary software to spot errors. 

2. You can customize code 

Perhaps one of the advantages of choosing open source is that it allows you to customize code to suit your business needs. Since the code is accessible, you can hire any programmer to configure the system for you. The programmer can go on and manipulate it for you until you are satisfied with the features of the system. 

3. It is affordable 

If you want to have an invoicing system without paying a monthly subscription, open-source is your answer. The main expense you will incur is only the maintenance of your system, which is usually pretty much reasonable.

Some business owners wonder how open source can be cost-effective. The answer is plain simple: 

Having open-source software is generally comes cheaper because businesses are not limited to one vendor for handling coding services. Countless programmers review the software for free. 

4. Open source invoicing solution gives you a competitive edge

The ability to invoice customers faster than your competitors without paying a subscription puts you in a great position to compete. And, you can customize each invoice to promote your brand. For instance, by adding your logo design on each invoice.

Here are some open source invoicing systems that you should consider:

1. Invoice Plane

InvoicePlane is one system that every business should use. This free and open-source invoicing application comes with a myriad of features that will make issuing invoices simple.  Even if you are not a bookkeeper, you won't find any trouble using it. 

Today Invoice Plane is available as an open-source and paid version. Both professionals and businesses can benefit from using InvoicePlane. Regardless you are a freelancer, small or medium-sized business. InvoicePlane is available in many languages, which means non-English speakers can use it as well. 


InvoicePlane comes with the following features:

  • InvoicePlane has an easy-to-use interface.
  • It makes invoicing clients easy.
  • It allows you to send quotes to customers.
  • It has a multi-language interface.
  • It supports one-click payments- you integrate it with online payment providers such as Paypal, Stripe, or Coinbase.
  • InvoicePlane allows you to track expenses.

2. Invoice Ninja

 Invoice Ninja is another highly recommended open source invoicing system. You will get a lot from this solution without paying anything, from world-class customer support to tons of features that will make invoicing your customers a breeze. If that is enough, you will also enjoy unique functionalities such as "buy now" eCommerce buttons and listening commands.

You can use it to process invoices online and get your payments faster from your customers. If you're unfamiliar with invoicing, there are four free invoice templates that you can use. You can also tailor your invoice by adding a logo, creating a PDF, and emailing your invoices with a click of a button.


Invoice Ninja offers the following features:

  • It allows you to attach files. 
  • You can add users and set permission levels. 
  • Invoice Ninja will enable users to add up to 20 users.
  • It comes with a feature that will allow you to attach Excel, Word Docs, and more. 
  • You can create quotes instantly.
  • It has a functionality that can customize Email Subjects and Body Text.
  • Invoice Ninja lets you customize colors to match your brand.
  • It has an encryption feature that secures your password.
  • You can create project tasks and track time online. 
  • The one-click feature allows you to process email invoices. 

3. Ledgersmb

Another unique open source invoicing system efficient for businesses is Ledger SMB. It comes with an ERP software program that can perform multiple functions, and you can use it to manage your operations, track invoices and payments, inventory, and more.

Thanks to Ledgersmb's versatile interface, you can integrate it with your other business applications. Customizing it is also easy; you can hire a programmer to modify or enhance its features as well.

If you are a startup, you can use general ledger and journal entry features and manage your cash flow. Furthermore, you can track budgets, run variance financial reports, send quotations, purchase orders, vendor orders, etc. 


Features of the Ledgersmb include the following:

  • You get a General Ledger and Journal Entry feature.
  • Ledgersmb allows you to manage your accounts and transfer money between them
  • Create a Sales report.
  • It has a feature that tracks quotes, sales orders, and invoices.
  • You can track vendors and purchase orders.
  • It supports multiple currencies. You can enter amounts using various currencies using different conversion rates.
  • You can manage contacts. 
  • Manage cash in and cash out. 
  • You can use it to reconcile with bank statements.
  • Manage your fixed assets, their depreciation, and disposal.
  • Create budgets for your business.

4. Dolibarr

Have you heard of Dolibarr ERP & CRM? It is open-source software that will help you manage your invoices like a pro. We like that it is easy to install for developers, and all they have to do is ask you which features you want; then, they can customize it for you. It comes with modules such as Human Resources, Marketing, Finance, and more. 


Features of the Dolibarr ERP include: 

  • CRM and sales – This feature allows you to manage contacts, create quotes, and process orders.  
  • Product and stock – You can use this feature to modify prices and product quantity.
  • Human resources – Use this feature to manage employee's leave, or approve reimbursement requests. 
  • Finance and billing – You can use this functionality to pull data into your general ledger. 

5. Open Source Billing 

Why pay proprietary software vendors to send an invoice if there is a solution for invoicing customers for free? Open Source Billing is an open-source invoicing system that lets you invoice clients. Receive payments, and track reports without paying a dime. 

This highly secure and PCI-compliant tool is suitable for any business, regardless of size or industry. You can use it to create and send invoices, track payments, download reports, and even receive payments via PayPal. 


  • It comes with an invoice dispute management feature.
  • An easy-to-use dashboard.
  • Allow you to track partial payments. 
  • You can use it to create and send invoices to customers. 
  • Send invoices via email. 
  • Export your invoices in PDF format.
  • It allows you to review the payment collected. 
  • You can view revenue by the client. 

6. Kill Bill

If you own a SaaS company, then you can benefit from using Kill Bill. It has all the essential features a SaaS business needs to run subscription billing processes. What is more, it is free, which means you can use it to grow your business without any worry of paying for software licensing fees.  

The most exciting part: Kill Bill allows you to create billing for each client. Every time you generate an invoice, you will know it is for a specific customer. You can hire a developer to customize it and plugins to make it more user-friendly for your business. 


Some key features of the Kill Bill invoicing system:

  • You can use it to create customized deployments.
  • Kill Bill has Java APIs and HTTP REST APIs that you can integrate with other applications or embedded as a library (Java APIs)
  • It supportssignificant Servlet containers, specifically Jetty, Tomcat, and more.
  • It allows route requests to various nodes.
  • You can use Kill Bill to manage your workload. 
  • It allows you to register webhooks and integrate with other applications on Zapier. 
  • It allows you to customize a system using Ruby and Java plugins.

7. Crater App

Another open-source invoicing solution that you should explore is Crater App. It is made in Laravel, VueJS & React Native, languages that enable it to track expenses, payments, and process invoices. You can use it to estimate quotes, offer discounts on invoices. Crate App will also come in handy if you calculate taxes per item or based on the invoice amount. 


CrateApp comes with the following features: 

  • It allows you to keep track of all your payments.
  • CreateApp will enable you to process and send invoices to customers. 
  • You will be able to generate reports anytime.
  • It comes with a feature that will allow you to track expenses. 


If you want to process your invoices faster than your competitors, getting an open-source invoicing is the way to go. Ultimately, you will receive payments on time and continue to send quotes to prospects. But only an open-source solution can help you achieve any of those goals. Before it can do any of this; it needs to be configured and customized properly. That's where a professional developer comes. 

Let's look at this scenario: Tom is the owner of TMZ Marketing, a digital marketing firm that services small to medium-sized businesses in LA. He invoices all his clients on the 20th of every month using Sage, a closed source invoicing system. Tom has noticed that using Sage costs his fledgling company an amount of $120 every month, as he has to pay for every user. Then one of Tom's employees suggests that they try an open-source invoicing system. He suggests Invoice Ninja, which will help them process invoices faster and get paid on time. Tom agrees, and his marketing business has been growing exponentially ever since. Tom and his team use one of four free invoice templates of Ninja Invoice to create professional invoices. He can now send invoices and use the same software to track payments. Life has never been easy for Tom!

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Amelia Walker
Amelia Walker
2 years ago

Hello. Nice Blog Thanks for sharing. You can also add Moon Invoice to your list as it's also the best option to use for invoicing.

1 year ago

I work at Lago, it's an Open Source Billing API for SaaS. 
It's great to handle hybrid pricing: when the pricing plan involves subscription and consumption-based charges. 
We connect to the most popular payment companies, like Stripe Payments.
It's backed by Y Combinator. 

Article By
James LePage
James LePage is the founder of Isotropic, a WordPress education company and digital agency. He is also the founder of, a venture backed startup bringing AI to WordPress creators.
We're looking for new authors. Explore Isotropic Jobs.
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