Is SaaS taxable? State by state
Whether software sold as a service is taxable depends on the state; nexus alone doesn't answer it.
Goods are taxable almost everywhere a sales tax exists. Software sold as a service isn't settled the same way: some states tax SaaS, some don't, some tax part of it or only business use, and a few have no clear rule. A SaaS company crossing a state's threshold has to check whether what it sells is taxable there before it has anything to collect. When a seller didn't charge tax that was due, the buyer owes use tax instead.
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