Nexus determines whether a state may require a filing; apportionment determines how much multistate business income is assigned there. The facts overlap, but the analyses are distinct. Product destinations, service markets and ledger revenue must meet in one controlled workpaper.
1. Separate nexus, allocation and apportionment
Nexus addresses filing jurisdiction. Allocation commonly assigns specific income to one state, while apportionment uses statutory factors to divide multistate operating income. A company may have nexus but little apportioned income; a high sales percentage does not eliminate the separate nexus or P.L. 86-272 analysis.
Many states emphasize a sales factor, but factor weights, property and payroll, combined reporting and special-industry formulas vary. Every workpaper should identify the state, tax year, filing group and official rule used.
2. Product sales usually begin with destination
For tangible goods, many states begin with where property is delivered or shipped to the purchaser. Marketplaces, 3PLs, drop shipments, customer pickup and cross-border logistics can separate billing address, ship-from location, ultimate destination and inventory ownership. Order systems need fields that preserve those distinctions.
Returns, discounts, freight, marketplace-collected tax and platform fees must follow a consistent receipts definition. Apportionment receipts are not bank deposits. Start with gross sales, apply state-authorized adjustments and bridge the result to financial-statement revenue.
- Order, selling entity and channel
- Ship-to, bill-to and actual delivery location
- Product, service, freight, tax and discount components
- Returns, cancellations, exchanges and period adjustments
- Marketplace and direct-channel gross-to-net bridge
3. Service receipts require the customer's market
Market-sourcing states may look to where the benefit is received, where delivery occurs or where the customer is located, often through a hierarchy and reasonable-approximation rules. Contract signature, invoice address, payment bank and employee location may be evidence, but none is a universal substitute for the customer's market.
For B2B services, identify using departments, users or operating sites. SaaS data may include subscription users or other reasonably available customer-location evidence. Professional services require attention to the deliverable and project benefit. If direct evidence is unavailable, document the approximation method and apply it consistently.
- Contract description and deliverable
- Customer entity, billing address and operating sites
- User, project or benefiting-function location
- Reasonable-approximation hierarchy for missing data
- Consistent method and approval for exceptions
4. Build an auditable numerator and denominator
First reconcile everywhere receipts to the filing group's ledger. Then classify products, services, licenses, interest and other items. Apply each state's sourcing rule to the numerator and separately document throwback, throwout, exclusions and special rules. Every adjustment should trace to transactions or a calculation memo.
Do not start each state with a different export. One controlled dataset can generate state views and exception reports for missing jurisdictions, conflicting addresses, negative revenue and cross-period returns. That improves both filing consistency and audit support.
5. Bring business changes into the model promptly
New products, subscriptions, distributors, contracts, fulfillment patterns and acquisitions can change classification and sourcing. Tax should help design revenue-master and contract fields, then review material changes at least quarterly rather than receiving only an annual summary.
Compare filed apportionment with operating metrics. Rapid state growth with a flat numerator, all service revenue assigned to headquarters, or a large unknown category can signal a data failure before it becomes a return position.
