The world of online billing and invoicing systems has proved to have a lot more breadth and depth than I had ever imagined. With countless billing and invoicing systems to choose from I have my work cut out for me if I am going to find the ultimate online billing system.

Each system has its own unique focus and strengths ranging from service provisioning , time tracking, accounting and tax related features, client management, multiple user orientated, added legal templates, branding and design orientated and many more.

Most of the systems contained in the list below are true online billing/invoicing systems, but I have included some download and install options for those who do not want a ‘ready-hosted’ system. I have also added a few payment gateways and accounting systems that allow for the creation and issuing of invoices, but lack the full range of features present in an online billing system, due to the fact that many of them are extremely fast to use and signup in many cases is free. So read on and marvel at the sheer range and diversity of systems!

• A Plus Bill
• AWBS (Formerly DRAMS)
• Ball Park
• BambooInvoice
• Bankoi Web Billing
• Bill4Time
• Billfaster
• Billflo
• Billing Boss
• Billing Manager (from Intuit)
• Billing Orchard
• Billings (For Mac users)
• BillingTracker Pro
• BillMyClients
• BillQ
• BillQuick
• Billy: The Billing Engine
• Black Sheep Invoices
• Blinksale
• CannyBill
• Cashboard
• Chargify
• Cheddargetter
• ClearBooks
• Curdbee
• Digitub
• Easy Bill Online
• Easyinvoice
• ePowerbilling
• Excel Invoice Manager
• Express Invoice
• Ezy Invoice
• FastDue
• FaktumInvoicing
  
• Fluttervoice
• FreeAgent
• Freelance Total
• Freelanceassistant.ca (only available to Canadian users)
• FreshBooks
• Greenbill
• Harvest
• Inflow Inventory
• inniAccounts
• Instant Invoice
• Intervals
• Invoice journal
• Invoice More
• Invoice my Work
• Invoice Quick
• Invoice.com
• Invoice2go
• Invoice4U
• Invoiceit!
• Invoiceplace
• Invoicera
• Invoices Made Easy
• Invoices on the run
• Invoices Online
  
• Invoicing System
• Invotrak
• IQ Business
• iScripts EasyBiller
• jBilling
• Juffler
• Kashflow
• kBilling
• Iris Accounting and ERP software
• Less Accounting
• Lite Accounting
• M & R Technologies
• Moobiz
• Net2Invoice
• Nett 30
• Ofuz
• Online Invoice System
• Openair
• Parallels Plesk Billing (Formerly ModernBill)
• PawBill
• PayPal Invoicing
• PaySimple
• PHP invoice
• Platypus ISP Billing
• Pocket Business Tools
• Quick Books Online
• Quick-billing
• QXInvoice
• Recurly
  
• Ronin
• Saasu.com
• SaaSy
  
• Sales King
• SantexQ
• Sbzone
• Side Job Track
• Simple Invoices
• Simplify This
• Simply Invoice
• Simply Invoices
• Simplybill
• Siwapp
• SliQ Invoicing
• Smart Invoice (formerly AcuInvoice)
• SnapBill
• Spreedly
  
• ST Web Invoice
• Subernova
• The Invoice Machine
• Time 59
• Trade Invoice
• Tradeshift
  
• Web Billing
• Winkbill
• WorkingPoint
• Xero
• Zoho Invoice

Have I missed any?

If you have developed or use a billing or invoicing system that is not on the list, please send me an email so I can update the list.