In our 29-criterion evaluation of software-as-a-service (SaaS) billing providers, we identified the nine most significant ones — Aria Systems, BillingPlatform, Chargify, Gotransverse, Recurly, RecVue, Salesforce, SAP, and Zuora — and researched, analyzed, and scored them. This report shows how each provider measures up and helps digital business strategy professionals select the right one for their needs.