Selling online does not keep your business outside state tax rules. A warehouse, employee, or growing volume of California orders can create an obligation to register and collect tax, even without a storefront. This guide explains sales tax nexus ecommerce requirements for California, how marketplace sales affect your obligations, and what to review before expanding into another state.
What sales tax nexus means for ecommerce sellers
Nexus is the connection between a business and a state that allows the state to impose tax obligations. For online sellers, that connection may arise from physical activity or the amount of business conducted with customers in the state. Incorporating elsewhere does not, by itself, prevent California tax obligations.
In South Dakota v. Wayfair, Inc., 585 U.S. 162 (2018), the U.S. Supreme Court rejected the rule that physical presence was always necessary before a state could require a seller to collect sales or use tax. States now apply their own economic nexus rules. There is no single nationwide threshold.
California businesses also need to distinguish sales tax from use tax. Sales tax generally applies to a retailer’s taxable California sales; use tax generally applies to taxable purchases used in California when sales tax does not apply. Depending on the transaction, an online retailer may have a sales tax reporting obligation or a duty to collect use tax.
A regulatory compliance review can help connect your sales channels, inventory locations, and customer destinations to the applicable registration requirements.
California’s $500,000 economic nexus threshold
Under California Revenue and Taxation Code section 6203(c)(4), a retailer is generally engaged in business in California when the total combined sales of tangible personal property for delivery in California by the retailer and all persons related to the retailer exceed $500,000 during the preceding or current calendar year. Related persons are defined in the statute. Marketplace sellers must also consider the registration and collection provisions in sections 6044 and 6045.
This is a sales-dollar test, not a transaction-count test. A seller can cross it through relatively few large orders. The calculation generally includes marketplace-facilitated sales and sales exempt from tax, not just taxable sales. Apply any statutory exclusions or limitations relevant to the particular transaction.
- Review both calendar years. Check the preceding year and monitor the current year as sales accumulate.
- Combine relevant channels. Include California deliveries through your website, direct orders, and marketplaces when calculating the threshold.
- Review related businesses. Separate entities may need to combine sales under the statutory related-person rules.
- Do not assume a grace period. Identify when registration and collection duties begin rather than waiting until year-end.
The threshold concerns tangible personal property. Digital products, services, and mixed transactions require separate classification; online delivery alone does not establish whether a sale is taxable.
Physical presence can trigger obligations below the threshold
The $500,000 threshold is not a safe harbor for every seller. A sufficient California physical presence can establish that a retailer is engaged in business in California even when California sales fall below that amount. California Revenue and Taxation Code section 6203 addresses connections such as business locations and representatives performing specified sales, delivery, installation, assembly, or order-taking activities in the state. The specific registration and collection obligations depend on the activity and transaction.
Common facts to investigate include:
- Inventory stored in California, particularly in dedicated, non-commingled storage at a third-party warehouse or fulfillment center. Review inventory ownership and the storage arrangement rather than treating every third-party location identically.
- An office, distribution location, or other California business facility.
- Employees or representatives performing relevant activities in California.
- In-state sales activities, installations, or other operations requiring a closer review.
Inventory placed in a marketplace fulfillment network deserves particular attention. The platform may move goods between warehouses without a seller selecting each location. Obtain inventory-location reports and review whether goods are commingled instead of assuming that your mailing address determines your footprint.
Physical presence can also affect local district tax obligations. A registration analysis should therefore examine both statewide rules and the places where your business operates.
Marketplace collection does not answer every nexus question
California’s Marketplace Facilitator Act generally makes a qualifying marketplace facilitator responsible for collecting and reporting tax on facilitated sales. That can reduce a marketplace seller’s collection responsibilities, but it does not erase every registration or recordkeeping issue.
A marketplace seller generally is not required to register with the California Department of Tax and Fee Administration as a retailer if all of its retail sales of tangible merchandise are facilitated by marketplace facilitators that are registered or required to be registered with the department and are responsible for those sales. Different obligations can apply when the seller also makes direct sales. Separate registration obligations, including qualified-purchaser or product-fee obligations, may still apply. Confirm the platform’s status and retain documentation showing which transactions it covers.
Marketplace-facilitated sales generally still count toward California’s $500,000 economic nexus threshold. However, exceeding the threshold solely through sales covered by the marketplace-seller registration exception does not, by itself, require the seller to register as a retailer. For example, a seller with $450,000 in marketplace sales and $75,000 in website sales delivered into California exceeds the threshold and generally must register and collect tax on its taxable direct sales, even if the facilitator collects tax on the marketplace portion.
Keep marketplace transactions separate from direct transactions in your records. Otherwise, you may overlook tax due on website orders or report tax twice on sales already covered by a facilitator.
Build a practical registration and monitoring process
A useful sales tax nexus ecommerce process starts with reliable data, not a checkout setting. Tax software can support calculations, but it depends on accurate product classifications, addresses, registrations, and business-location information.
- Map your footprint. List inventory locations, employees, facilities, marketplaces, and direct sales channels.
- Track destination sales. Monitor California deliveries and each other state’s separate nexus rules.
- Confirm registration requirements. Determine the appropriate California Department of Tax and Fee Administration registration before collecting tax.
- Configure tax collection. Review product taxability, exemption documentation, and applicable district taxes.
- Maintain records and filing deadlines. Reconcile marketplace reports, direct sales, returns, and tax payments.
If your business crossed a threshold earlier, investigate the exposure before assuming that registration resolves past periods. Prior tax, interest, and penalties may require separate attention.
Talk to a California business attorney
Itkin Law offers a free consultation to discuss your online sales operations and California compliance questions. Schedule a free consultation or call (424) 603-8888.
This article is attorney advertising and provides general information only. It is not legal advice and does not create an attorney–client relationship. The law changes, and this article reflects the law as of its publication date. Every situation is different — contact us to discuss how the law applies to your exact circumstances. See our full disclaimer.
