Sales tax answers for
ecommerce businesses.
Plain-language answers to the questions ecommerce operators actually run into — nexus thresholds, product taxability, exemption certificates, filing deadlines, audits, and more.
No vendor pitch. No hedging. Direct answers for founders, controllers, and finance teams.
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View all →Sales Tax Basics
Foundational concepts every online seller needs to understand.
15 questionsEconomic Nexus
Wayfair thresholds, state-by-state rules, and what to do when you cross one.
17 questionsPhysical Nexus
FBA inventory, 3PL warehouses, remote employees, and trade shows.
13 questionsSST Program
How the Streamlined Sales Tax program works and why CSP certification matters.
11 questionsSwitching Providers
How to leave Avalara, TaxJar, or Numeral without a compliance gap.
11 questionsRegistration & Permits
How to register, what it costs, timelines, and late registration recovery.
13 questionsFiling & Deadlines
Filing frequencies, deadlines by state, zero returns, and multi-state filing.
13 questionsProduct Taxability
SaaS, digital goods, clothing, food, shipping, gift cards, and more.
22 questionsMarketplace Facilitators
Amazon, Etsy, eBay, Walmart, TikTok Shop — what they handle and what they don't.
16 questionsExemption Certificates
Resale certs, B2B exemptions, multi-state certificates, and validation.
19 questionsAudits & Penalties
VDA process, audit triggers, penalty rates, and how to get current.
22 questionsState Guides
Nexus thresholds, filing rules, and key taxability notes for all 50 states.
57 questionsEcommerce Platforms
Shopify, WooCommerce, BigCommerce — what they handle and how to integrate.
17 questionsComparisons
TaxCloud vs. Avalara, TaxJar, Numeral, Kintsugi, and more.
15 questionsMid-Market & Scaling
Managing compliance across 30+ states, M&A implications, and cost analysis.
12 questionsFeatured questions
When do I have to start collecting sales tax in another state?
You must collect sales tax in another state once you have nexus there, triggered by physical presence or crossing a $100K sales threshold. Here's exactly when your obligation starts.
What is the Streamlined Sales Tax (SST) program?
The SST program is a 24-state cooperative that lets remote sellers handle compliance in member states for free through a Certified Service Provider. Here's exactly how it works.
How do I cancel my Avalara contract?
Canceling Avalara requires written notice before your renewal date. Miss the window and you're locked in for another term. Step-by-step guide including SST state transfers and data export.
I haven't been collecting sales tax — what do I do now?
You have three options when you realize you haven't been collecting sales tax: register and pay retroactively, pursue a Voluntary Disclosure Agreement, or do nothing. Only one of these resolves your exposure cleanly.
Which sales tax plugins work best with WooCommerce?
The main certified sales tax plugins for WooCommerce are TaxJar (now part of Stripe), Avalara AvaTax for WooCommerce, and TaxCloud (via API connector). Each offers automated rate calculation at checkout. TaxJar has the most seamless WooCommerce-native experience. Avalara has the most enterprise feature depth. TaxCloud provides SST CSP certification and is the only SST-certified option.