California Sales Tax Nexus: The $500,000 Threshold Explained for Online Sellers (2026)

A remote seller has California sales tax nexus once its total combined sales of tangible personal property for delivery into California, together with sales by related companies, exceed $500,000 in the preceding or current calendar year. There is no transaction-count test, and the rule lives in Revenue and Taxation Code §6203(c)(4).

The threshold comes from AB 147, signed April 25, 2019 and made operative back to April 1, 2019, which superseded the CDTFA's initially announced standard of $100,000 or 200 transactions. It is measured on calendar years, not a rolling 12 months. If you passed $500,000 of California deliveries in 2025, you are engaged in business in California for all of 2026. If you pass it partway through 2026, the obligation starts on the day you cross, and CDTFA's guidance says you are not liable for tax on earlier sales.

Three details catch sellers out:

• The total counts nontaxable sales of tangible goods too, including sales for resale. A wholesaler with $600,000 of resale-certificate sales into California is over the line even if it never collects a dollar of tax.
• Sales you make through a marketplace facilitator (Amazon, Walmart, Etsy) count toward your own $500,000, per CDTFA's Marketplace Facilitator Act guide.
• Only sales of tangible personal property count. Revenue from SaaS or services that are not part of a sale of goods does not.

The $500,000 test is only one way into California. Under §6203(c), a retailer is also engaged in business in the state if it has an office, warehouse or other place of business there, or has employees, agents or representatives operating in California, regardless of sales volume.

For startups the usual triggers are a remote employee living in California, inventory stored in a California fulfillment center (including Amazon FBA warehouses), or a trade-show booth staffed by your team. Any one of these means you should register and collect on taxable sales from the first dollar.

This is the first question we ask in a nexus determination: where are your people and your inventory? The sales-volume math comes second.

Usually there is nothing to collect. California generally does not tax SaaS before January 1, 2027, when SB 122 adds SaaS and other digital products to the sales tax base, because access to software running on the vendor's servers is not a transfer of tangible personal property. Under Regulation 1502, custom software is not taxable in any form, and prewritten software delivered electronically is not taxable when the buyer receives no tangible copy (no disk, no preloaded device).

Because SaaS revenue is not a sale of tangible property, it also does not count toward the $500,000 threshold. A pure SaaS company with California employees may technically be engaged in business in the state, but if it sells nothing taxable it has no sales tax to remit.

The answer changes when you sell hardware, ship software on physical media, or bundle devices with a subscription. Hardware-as-a-service models and IoT products need a line-by-line review, because the tangible part is taxable and can pull part of the bundle with it.

The statewide base rate is 7.25%. On top of that, voter-approved district taxes each add between 0.10% and 2.00%, and some areas have more than one, so combined rates in a number of cities, including parts of Los Angeles County, are above 10%. Rates change quarterly (the current schedule took effect October 1, 2026).

Once you exceed the $500,000 statewide threshold, you are treated as engaged in business in every district, so you collect the full combined rate at the customer's delivery address. That means address-level rate lookup for every California order. Use CDTFA's rate lookup to spot-check, and use a tax engine (Avalara, TaxJar, Anrok, or your platform's built-in calculation) for the checkout itself. ZIP-code-only rates are often wrong in California because district boundaries do not follow ZIP codes.

Out-of-state retailers register with the CDTFA for a Certificate of Registration – Use Tax, the permit used to collect California use tax from customers. A business with a physical location in California registers for a seller's permit instead. Registration is online through CDTFA's website.

If every one of your California sales goes through a registered marketplace facilitator, you generally do not need to register at all, because the marketplace collects and remits. The moment you also sell direct (your own Shopify store, wholesale), you need your own registration if your combined sales exceed $500,000.

After registration, CDTFA assigns a filing frequency based on expected tax. Quarterly returns are due on the last day of the month after the quarter ends: April 30, July 31, October 31 and January 31. A late return or late payment carries a 10% penalty plus interest.

If you crossed the threshold in an earlier year and never registered, the exposure runs further back than most founders expect: CDTFA generally has eight years from the return due date to assess a non-filer, versus three years once returns are filed. A voluntary disclosure request is usually the cleaner way to come forward, and it is worth modelling before you register.

Most ecommerce sellers deal with only a few exemptions. Groceries are exempt but hot prepared food is not. Prescription medicines are exempt under §6369. Qualifying manufacturing and research-and-development equipment gets a partial exemption from the state portion of the rate under §6377.1, which hardware startups often overlook on their own purchases.

Sales for resale are exempt when the buyer gives you a valid resale certificate (CDTFA-230). Collect it before or at the time of sale and keep it on file; an auditor will disallow resale sales without one.

Regulation 1698 requires you to keep sales and use tax records for at least four years, longer if an audit, appeal or refund claim is open. Keep resale certificates, exemption documents and marketplace reports for the same period.

1. Total your California deliveries of tangible goods for last year and this year to date, including exempt sales, resale sales and marketplace sales.
2. Check for physical presence: employees, contractors acting for you, inventory in California warehouses.
3. If you are over $500,000 or have presence, register with CDTFA before you start collecting.
4. Classify every product. SaaS and custom software are generally not taxable; hardware and physical media are.
5. Set up address-level rate calculation for direct sales and confirm the marketplace is collecting on marketplace orders.
6. Put quarterly due dates and resale-certificate collection on a calendar.

We do this work as a nexus study: map where you have sales and people, determine which states you must register in, quantify any back exposure, and decide whether a voluntary disclosure makes sense. Rules here were checked against CDTFA guidance in October 2026. This is general information, not tax advice for your specific facts.