Guides a business through the full US sales and use tax lifecycle: economic nexus analysis under South Dakota v. Wayfair, state registration (including SST centralized registration), exemption certificate collection, return preparation, and voluntary disclosure for back-period exposure. Produces a nexus matrix, registration checklist, and filed state sales tax returns.
Determine in which states the business has created sales tax nexus — both physical (offices, employees, inventory, trade-show attendance) and economic (post-Wayfair revenue/transaction thresholds). Flag states where the seller may already be delinquent. Note that five states have no general sales tax (AK, DE, MT, NH, OR) but may have alternative taxes (Alaska local taxes, Delaware GRT, NH Meals & Rooms Tax) that still require attention.
Register the business for a seller's permit or sales tax licence in every state where nexus has been confirmed. Use the Streamlined Sales Tax (SST) centralised registration portal (sstregister.org) for the 24 SST member states to reduce administrative burden. Register directly with each remaining state's department of revenue. Determine the correct filing frequency (monthly, quarterly, annual) assigned by each state based on expected liability.
Map every product SKU and service line to the correct taxability treatment in each nexus state. Key classification issues include: SaaS and digital goods (taxable in NY, TX, WA, PA, CT and ~17 others; exempt in CA, IL, CO, VA and others); unprepared grocery food (exempt in most states, taxable in AL, MS, SD, HI); clothing (exempt in PA, NJ, MN; threshold exemption in NY under $110/item and MA under $175/item); and manufacturing equipment (broadly exempt). Collect and file valid exemption certificates (Streamlined Sales Tax exemption form or state-specific form) for all exempt purchasers.
Prepare and file periodic sales and use tax returns in each nexus state. Source sales data from the accounting system or e-commerce platform, segregate by destination state and taxability classification, and reconcile collected tax against amounts remitted. Note that marketplace facilitator laws now cover all 45 sales-tax states plus DC — for marketplace-facilitated sales the marketplace collects and remits, so the seller reports only direct sales. Flag any state where collected tax differs from liability (over-collection or under-collection).
For states where nexus existed before the registration date, quantify the prior-period tax liability (typically limited to a 3–4 year lookback under most state VDA programs) and evaluate voluntary disclosure agreement (VDA) options. VDAs typically waive penalties and limit the audit lookback period; most states participate via the Multistate Tax Commission (MTC) anonymous VDA programme or their own state programme. If VDA is not available or the exposure is imminent (audit notice received), compute back-tax plus interest and prepare amended or late returns.
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no-sales-tax-states
Use this skill whenever asked about states with no sales tax, Alaska local sales tax, Dela
us-sales-tax
Use this skill whenever asked about United States sales tax, use tax, sales tax nexus, mul
us-sales-tax-nexus-50-state-matrix
Tier 2 US federal-level reference skill providing the post-Wayfair economic-nexus threshol