Amazon Case in South Carolina Pits Old Tax Laws Against New Tech

A case before the South Carolina Supreme Court that could cost Amazon Services LLC around $150 million shines a spotlight on problems that can arise when states try to apply pre-internet tax law to online platforms.

The e-commerce giant will ask the state justices during oral arguments Wednesday to reverse a 2024 appeals court ruling that it owes taxes on third-party sales for three months of 2016, before the state passed a law explicitly imposing tax obligations on online marketplaces.

The total bill for those three months came to more than $12.5 million in taxes, penalties, and interest. A ruling ...