The California throwback rule, found in Revenue and Taxation Code Section 25135, pulls certain out-of-state sales back into your California sales factor when the destination state cannot legally tax your company. If goods ship from a California location into a state where you lack nexus, those receipts count as California sales for apportionment. Because California uses a single-sales-factor formula weighted 100% on sales, every dollar thrown back raises the share of your business income exposed to the 8.84% corporate franchise tax.1State of California Franchise Tax Board. Business Tax Rates
When the Rule Applies
Section 25135(a) sets two conditions, and both must be met before a sale gets thrown back. The property has to ship from a California office, warehouse, factory, or other storage location, and the seller has to be not taxable in the state where the buyer sits.2California Legislative Information. California Revenue and Taxation Code Section 25135 A sale shipped from a Nevada warehouse into a non-nexus state stays out of California’s numerator. A sale shipped from California into a state where you do have nexus stays assigned to that destination state under ordinary rules. The statute also sweeps in sales to the U.S. government shipped from California, under the same subsection.
One narrow boundary matters at the outset: the rule reaches only tangible personal property. Service revenue and intangibles follow market-based sourcing under Section 25136, which has no throwback mechanism. If your California firm bills a consulting fee to a Texas client, that revenue goes to Texas whether or not you have nexus there.3Legal Information Institute. California Code of Regulations Title 18 Section 25136-2 Service businesses and software licensors generally sit outside the throwback problem; manufacturers and distributors of physical goods carry its full weight.
What “Not Taxable in Another State” Means
The second trigger turns on a legal definition that is broader than most sellers assume. Under R&TC Section 25122, you are taxable in another state if either of two things is true. First, you are actually subject to that state’s net income tax, franchise tax measured by net income, franchise tax for the privilege of doing business, or corporate stock tax. Second, that state has the legal jurisdiction to impose a net income tax on you, whether or not it does.4California Legislative Information. California Revenue and Taxation Code Section 25122
That second test does the work. You do not have to file a return in the destination state or pay anything there. If the state could tax you based on your activities, California treats you as taxable and throwback does not apply. The reverse is also true: filing voluntarily in a state that lacks jurisdiction over you, or paying a non-qualifying tax type, will not stop throwback.
Public Law 86-272: The Usual Reason You End Up Non-Taxable
The most common reason a company lacks taxing jurisdiction in a destination state is the federal shield in Public Law 86-272. The statute bars a state from imposing a net income tax on an out-of-state company whose only in-state activity is soliciting orders for tangible personal property, provided the orders are sent outside the state for approval and filled by shipment from outside the state.5Office of the Law Revision Counsel. 15 USC 381 – Imposition of Net Income Tax If your California-based seller only sends sales reps into a state to take orders, that state cannot tax you, and that same shield is what pulls the sale back to California.
The federal protection is narrow in two ways. It covers only tangible personal property, so services, software licenses, and other intangibles never qualify. And it disappears the moment employees do anything beyond solicitation in the destination state, such as installing products, providing technical support, or handling warranty repairs.6Multistate Tax Commission. Statement of Information Concerning Practices of Multistate Tax Commission and Signatory States Under Public Law 86-272
Internet Activities Are Contested Ground
Whether routine online interactions exceed solicitation has become a live fight. The Multistate Tax Commission’s revised 2021 statement takes the position that virtual contacts with a state’s residents can be business activities beyond solicitation, drawing on the Supreme Court’s reasoning in South Dakota v. Wayfair.7Multistate Tax Commission. Statement of Information Concerning Practices of Multistate Tax Commission and Supporting States Under Public Law 86-272 Several states have adopted regulations treating specific digital activities as unprotected, including placing cookies for market research, offering live chat, and accepting job applications through a website.
California’s own effort was Technical Advice Memorandum 2022-01, which identified nine internet activities the Franchise Tax Board considered unprotected. A San Francisco Superior Court struck the TAM down in December 2023, finding it was an underground regulation adopted without the required Administrative Procedure Act rulemaking.8Ernst & Young. California Superior Court Finds FTBs PL 86-272 TAM and Publication to Be Invalid Underground Regulations The guidance is technically invalid, but reports indicate FTB auditors continue applying its principles in examinations. Companies claiming P.L. 86-272 protection in states where they maintain significant online customer interactions should expect scrutiny, and that scrutiny feeds directly into whether sales get thrown back.
The Finnigan Rule for Combined Groups
Many California corporate taxpayers file as part of a combined reporting group covering a unitary business. For tax years beginning on or after January 1, 2011, California applies the Finnigan rule, codified in Section 25135(b). The throwback analysis looks at the entire combined group. If any member of the group is taxable in the destination state, the sale stays assigned there.2California Legislative Information. California Revenue and Taxation Code Section 25135 A sale gets thrown back only when no member of the group is taxable in the buyer’s state.
For large groups with diverse operations, this materially reduces throwback exposure, because the odds that at least one affiliate has nexus somewhere are much higher than the odds for any single entity.
Double Throwback for Drop Shipments
A more aggressive version of the rule applies when goods never pass through the seller’s facilities. Suppose your California sales office directs a third-party manufacturer in Colorado to ship product straight to a customer in Arizona. If you lack nexus in Arizona, normal throwback would send the sale to Colorado as the state of shipment. If you also lack nexus in Colorado, the sale has nowhere to land, and California’s regulation reassigns it to California as the state where the sales activity originated. That is the double throwback rule.9Franchise Tax Board. Multistate Audit Technical Manual Chapter 7500 – Sales Factor
What Throwback Costs You
California’s apportionment formula for most corporations is a single sales factor: California sales divided by total sales everywhere, multiplied by apportionable business income.10California Legislative Information. California Code RTC 25134 Throwback grows the numerator without changing the denominator. A simplified example shows the arithmetic.
- Total sales everywhere: $10,000,000
- Sales delivered to California customers: $3,000,000
- Sales shipped from California to states where no group member is taxable: $2,000,000
- Total apportionable business income: $5,000,000
Without throwback, the California sales factor is $3,000,000 / $10,000,000, or 30%. Income taxable in California is $1,500,000, and tax at 8.84% is $132,600.
With throwback, the $2,000,000 moves into the California numerator. The factor becomes 50%, income taxable in California rises to $2,500,000, and tax at 8.84% is $221,000. That is $88,400 in additional California tax attributable entirely to throwback.
The effect scales with how much product leaves California bound for states where you have no footprint. A manufacturer that ships nationwide from a California plant while keeping a thin presence elsewhere can see its California apportionment factor climb well above what pure destination sourcing would produce.
Reducing Your Exposure
Companies facing meaningful throwback usually look at a few options.
The most direct is establishing nexus in destination states so the “not taxable” condition fails. Filing a return in another state can sound backwards, but if that state’s rate sits below California’s 8.84%, the net result can favor the taxpayer. Some states also permit voluntary nexus elections.
Another is shipping from outside California. If goods leave a Nevada or Texas warehouse rather than a California one, the first throwback condition is not met and the rule does not apply. The Tax Foundation has documented companies relocating distribution operations out of throwback states for exactly this reason.11Tax Foundation. State Throwback Rules and Throwout Rules: A Primer The real-world costs of running warehouses in multiple states have to be weighed against the tax savings.
For combined groups, Finnigan creates structural room to maneuver. Because throwback requires that no member of the group be taxable in the destination state, extending any single affiliate’s activities in that state far enough to create nexus can eliminate throwback for every member shipping there.2California Legislative Information. California Revenue and Taxation Code Section 25135 The whole group’s nexus footprint becomes a planning variable, not just the footprint of the selling entity.