California Sales Tax Nexus Rules and Your Registration Start Date

Merchandise stored in California can create physical nexus below the economic threshold. Use warehouse and fulfillment reports to identify when you first held inventory there. Preserve ownership records and transfer dates. Marketplace-only sellers should also apply the registration exception discussed below.

Remote sellers shipping from outside the state generally collect use tax on taxable sales. Stocking and selling merchandise within the state may require a seller's permit instead. Confirm the account with the California Department of Tax and Fee Administration (CDTFA). This state and local tax inquiry is separate from corporate qualification and income tax filing.

For a November 2026 review, prepare a complete 2025 total and a 2026 year-to-date total. Do not combine the two years, use a rolling 12-month period, or count only Black Friday orders.

If 2025 already exceeded the threshold, low early-2026 sales do not create a fresh exemption. Review the earlier crossing date and any intervening obligations. If neither year's sales exceed the threshold, physical presence still requires separate consideration.

Use invoices and fulfillment records to identify merchandise sold for delivery in California. A customer's billing address alone may not establish the delivery destination. Flag conflicting addresses and split shipments for review rather than assigning the entire order by the account profile.

Include qualifying exempt merchandise sales, such as sales for resale. Include sales by related persons as defined through Internal Revenue Code section 267(b). That federal cross-reference defines the relevant relationships for this state-law test. It does not turn the sales threshold into a federal tax rule.

Use underlying sales records rather than deposits reduced by fees, commissions, or reserves. Link returns and refunds to the original order, preserving both dates and amounts. A returned-merchandise deduction on a tax return does not, by itself, establish that a previously triggered registration duty disappeared. Review adjustments separately before changing the crossing date.

A seller whose retail sales are exclusively facilitated by marketplaces registered with CDTFA generally qualifies for an exception from seller registration. Retain the facilitator agreement and evidence of registration and tax responsibility.

Adding direct sales changes the result when physical or economic nexus already exists. A seller that exceeded the threshold through marketplace sales cannot wait for website sales alone to exceed $500,000. Review registration before the first direct sale. A payment processor is not automatically a marketplace facilitator.

Separate threshold inclusion from collection responsibility by sales channel.

Sort qualifying sales chronologically and calculate a running calendar-year total across channels. Identify the first transaction that brings the total above $500,000. Reaching exactly $500,000 does not meet the statutory requirement to exceed that amount.

If economic nexus first arises during the year and no marketplace-only exception applies, Regulation 1684 requires registration and collection immediately after the crossing sale. The newly triggered duty generally applies to subsequent taxable sales, rather than the crossing transaction. An earlier duty based on physical presence changes this analysis.

Keep the review materials together:

• Separate prior-year and current-year schedules with delivery destinations and running totals.
• Direct and marketplace channel labels, including facilitator responsibility records.
• Inventory locations, ownership records, and the dates storage began.
• Related-person sales schedules and notes explaining adjustments.
• Business identity, ownership, location, and sales-start information needed for registration.

As part of business compliance, assign someone to review new fulfillment locations and channel changes as well as revenue growth.

If the records reveal an earlier unregistered period, preserve the source data and determine which sales fell within it. Starting collection now does not resolve prior filing exposure. An attorney can assess the timeline, account requirements, and available correction procedures.

For a remote seller registered under Regulation 1684, a qualifying year generally carries registration into the following calendar year. If the threshold is exceeded in 2026, lower sales in 2027 alone do not end that duty. Before closing an account, review physical presence, prior-year sales, and any applicable exception through your state tax compliance process.