How do you handle US sales tax in Magento?

Magento ships with basic table-rate tax, which is fine for a single-state store. The moment you have economic nexus in more than one state — very common after Wayfair v. South Dakota (2018) — you need a real tax engine. We integrate TaxJar, Avalara AvaTax, or Vertex depending on your scale and budget. The engine pulls live rates per state, county, and even ZIP+4, files returns automatically, and keeps a full audit trail.