Whether your company is taxable in other states depends on whether you have nexus, or a presence, there. Nexus laws vary by state. The links below contain information to help you determine if you may have tax issues in other states:

North Carolina

Tennessee has no income tax but has a sales tax and franchise tax. See their FAQ for details.

Alabama uses a bright line test to decide nexus. It sounds good, but it’s broad and it’s very easy to establish nexus without intending to. Know the rules if you’re skirting nexus in Alabama.

South Carolina has established that the use of intangibles like trademarks establishes sufficient nexus for taxation. The case is Geoffrey, Inc. v. South Carolina Tax Commission. Geoffrey is a wholly owned subsidiary of Toys ‘R Us and collects a royalty for the use of those trademarks. Geoffrey now pays South Carolina tax on that royalty income.  Here’s South Carolinas nexus law.