I have been working a project to try and get some backend data plugged into QuickBooks so we can push that data into QuickBooks. We are using desktop QuickBooks hosted by another provided so our integration options are limited. We ended up using the QuickBooks Web Connector. First let me say that documentation on this front is limited and what you can find is normally old. Here is some of the reference we were able to find: Web connector overview QuickBooks error codes Helpful UI for how to construct QuickBooks API calls Web connector SDK QBWC Dev Guide You will need to create a QWC file and here is a QWC Example . One of the biggest issues we ran into was all the documents and examples we could find were based on the older ASMX services. Because of this we struggle for a bit on understanding how the service needed to be attributed. So here is what our WCF service contract ended need to be set as. [GeneratedCode( "wsdl" , "4.6.57.0" )]