## Sales tax nexus in Wisconsin Before 2018, businesses only had to collect sales tax in states where they had a **physical presence** (offices, employees, warehouses). The Supreme Court's **Wayfair v. South Dakota (2018)** decision changed that — letting states require tax collection based on **economic nexus** (volume of sales). ### Wisconsin sales tax - **Rates:** 5% state + local (avg combined ~5.7%) - **Economic-nexus threshold:** $100K sales ## What "nexus" means Nexus is the connection that makes you taxable in a state. Two main types: **Physical nexus:** - Office, warehouse, retail location - Employees in the state - Inventory in the state (FBA / Amazon warehouses count) - Salespeople / representatives - Trade-show attendance (some states) - Trucks / vehicles in the state **Economic nexus** (post-Wayfair): - Crossing dollar threshold of in-state sales - Crossing transaction-count threshold - Most states use $100K sales OR 200 transactions - Some states use higher thresholds (CA $500K, NY $500K + 100 tx, TX $500K) - Some states removed the transaction prong (ND, SD, TN, MN partially) ## Common physical-nexus traps - **Inventory in third-party warehouses** — Fulfillment by Amazon (FBA) creates physical nexus in every state where Amazon has a warehouse - **Affiliate / click-through nexus** — pre-Wayfair concept that some states still apply - **Marketplace facilitator laws** — Amazon, eBay, Etsy now collect on behalf of sellers in most states - **Drop-shipping** — physical presence at supplier creates issues - **Remote employees** — even one remote employee creates nexus - **Visiting on business** — extended visits, conferences, sales calls ## Marketplace facilitator laws Most states now require **marketplace facilitators** (Amazon, eBay, Walmart, Etsy, etc.) to collect sales tax on sales made through their platforms. This: - Shifts collection responsibility from individual sellers to the marketplace - Lets sellers cross thresholds without registering individually if all their sales go through marketplaces - Creates compliance simplification for many small sellers BUT — sales made off-marketplace (your own website, in-person, wholesale) still trigger nexus separately. ## Streamlined Sales Tax Project (SST) 24 states have signed onto the **Streamlined Sales Tax** initiative — providing simplified registration, uniform definitions, and free tax-calculation services. Member states include AR, GA, IN, IA, KS, KY, MI, MN, NE, NV, NJ, NC, ND, OH, OK, RI, SD, TN, UT, VT, WA, WV, WI, WY. ## What's taxable vs exempt **Generally taxable:** - Tangible personal property (most goods) - Some services (varies dramatically by state) - Software (varies — sometimes only canned, sometimes also custom) - Digital goods (varies — increasingly taxed) - Restaurant meals - Lodging **Often exempt:** - Groceries (varies; some states fully exempt, some reduced rate, some fully tax) - Prescription drugs - Medical equipment (varies) - Newspapers / magazines (varies) - Resale (B2B with valid certificate) - Manufacturing inputs (varies) - Casual / occasional sales (yard sales, etc.) - Sales to charitable organizations (with certificate) ## Sales tax compliance Once nexus is established: 1. **Register** with the state tax agency 2. **Charge correct tax rate** at point of sale (location-based; complex) 3. **Collect from customers** 4. **File returns** monthly, quarterly, or annually based on volume 5. **Remit collected tax** with returns 6. **Keep records** for 3-7 years depending on state 7. **Respond to audits** — sales tax audits are common, especially for ecommerce sellers ## Penalties for non-compliance - **Back taxes** — owed for entire period of unfounded liability - **Interest** — typically 5-12% annually - **Penalties** — often 5-25% on top of unpaid tax - **Personal liability** for responsible officers / owners (TX, CA, NY, others) - **Criminal charges** in willful cases ## Sales-tax software Modern compliance is generally tool-driven: - **Avalara** — comprehensive nexus tracking, calculation, filing - **TaxJar** — popular for ecommerce - **Vertex** — enterprise-level - **Sovos** — enterprise / complex - **State-provided free tools** — limited but helpful for small sellers ## What you should do If you sell into Wisconsin from out of state — or you're a Wisconsin seller wondering about your obligations elsewhere — review nexus carefully. Most Wisconsin sales-tax issues benefit from a CPA or sales-tax-specialist consultation. Many state tax agencies offer voluntary disclosure agreements (VDAs) for catching up on past obligations with reduced penalties. --- *This guide is general information about Wisconsin sales tax as of early 2026 and is not legal or tax advice. Sales tax law changes frequently and rates are updated. Consult a CPA or tax attorney for your specific situation.*