California Sales Tax Nexus Checker — 2026

The California economic nexus threshold is $100,000 in revenue measured over the previous or current calendar year. Once you cross this threshold, you must register with California, collect California sales tax on all taxable sales, and file regular returns. Marketplace sales through Amazon, Etsy, and similar platforms count toward the $100,000 threshold.

California Sales Tax Nexus — Frequently Asked Questions

What is the sales tax nexus threshold in California?

The economic nexus threshold in California is $100,000 in sales revenue during the previous or current calendar year. Once you exceed this amount, you are required to register with California and begin collecting sales tax on all taxable sales to California customers.

How does California measure the economic nexus period?

California uses the previous or current calendar year as its measurement window. This means if you exceed $100,000 at any point during the current calendar year, you have nexus immediately — you do not need to wait until the following year to register. Monitor your California revenue in real time.

Does California include marketplace sales in the nexus threshold?

Yes. California includes marketplace sales in its economic nexus threshold calculation. Sales you make through Amazon, Etsy, or other marketplace facilitators count toward the $100,000 threshold alongside your direct-channel sales.

How do I register for sales tax in California?

Register online at California's official tax portal: https://register.cdtfa.ca.gov/. Have your federal EIN, business legal name, mailing address, and anticipated first taxable sale date ready. Most states complete registration instantly and issue a permit number you can use immediately.

What happens after I exceed the California nexus threshold?

Once you meet the California economic nexus threshold, you must register, collect the correct California sales tax rate on all taxable sales, file regular returns (frequency depends on your sales volume — monthly, quarterly, or annually), and remit the collected tax by each due date. Retroactive liability can apply to sales made after you crossed the threshold but before you registered, so acting quickly after exceeding the threshold limits your exposure.