Texas adopted new regulations confirming that marketplace seller fees and commissions are taxable as "data processing services." These regulations take effect October 1, 2025, and will only be enforced prospectively. The state will require marketplaces to collect sales tax on the commission fees they charge to sellers, adding an 8%+ tax burden on top of existing marketplace fees. 

The bottom line: Marketplace sellers based in Texas will see their net revenue decrease as platforms like Amazon must now charge sales tax on commission fees. Marketplaces face significant administrative challenges, including issuing separate invoices for fees and handling complex sourcing rules that treat goods and commissions differently. Tax engines will need major updates to comply with these split-transaction requirements.