If you run a U.S. C corporation that sells software to customers in Berlin, licenses patents to a manufacturer in Seoul, or ships hardware from a warehouse in Ohio to a distributor in Mexico City, the federal government has been quietly handing you a discount for nearly a decade — and most eligible corporations never claim it.
The discount lives inside Internal Revenue Code Section 250, formerly known as the Foreign-Derived Intangible Income (FDII) deduction and now rebranded as the Foreign-Derived Deduction Eligible Income (FDDEI) deduction under the One Big Beautiful Bill Act (OBBBA). For tax years beginning before 2026, qualifying export income gets taxed at an effective federal rate of just 13.125% — roughly 38% lower than the standard 21% corporate rate. For tax years beginning after December 31, 2025, the effective rate ticks up to about 14%, and several technical mechanics change in ways that will help some corporations and hurt others.
This guide walks through who qualifies, how the new math works, what counts as a "foreign person" or "foreign use," what documentation the IRS expects, and the most common mistakes that wipe out the deduction during an audit.
What Section 250 Is Really Doing
Section 250 was enacted as part of the 2017 Tax Cuts and Jobs Act to encourage U.S. multinationals to keep their valuable intangibles — patents, software, trademarks, customer relationships — onshore rather than parking them in Ireland or the Cayman Islands. The mechanism is simple in principle: take a slice of corporate income that's "earned" from foreign customers, allow a generous deduction against it, and let the residual be taxed at the regular corporate rate.
For taxable years beginning before January 1, 2026:
- The deduction equals 37.5% of FDII.
- That produces an effective federal rate of 21% × (1 − 37.5%) = 13.125% on qualifying foreign-derived income.
- A parallel deduction equal to 50% of GILTI (Global Intangible Low-Taxed Income) reduces the effective rate on offshore CFC profits to 10.5%.
For taxable years beginning after December 31, 2025, OBBBA reshuffled the deck:
- FDII is renamed FDDEI and the deduction drops to 33.34%, producing an effective rate of approximately 14%.
- GILTI is renamed NCTI (Net CFC Tested Income) and its deduction is similarly trimmed.
- The Qualified Business Asset Investment (QBAI) "deemed routine return" offset is eliminated, simplifying the formula significantly.
- Interest expense and R&E (research and experimentation) expenditures no longer have to be allocated against eligible income — a major win for technology and pharmaceutical exporters.
Both regimes are accessed through the same form: IRS Form 8993, Section 250 Deduction for Foreign-Derived Intangible Income (FDII) and Global Intangible Low-Taxed Income (GILTI), which is filed as an attachment to the corporation's Form 1120.
Who Can Actually Claim It
The eligibility rules are narrower than most business owners realize. The Section 250 deduction is only available to:
- Domestic C corporations (filed on Form 1120), and
- Individuals who make a Section 962 election to be taxed at corporate rates on CFC income.
Specifically excluded: S corporations, partnerships and LLCs taxed as partnerships, sole proprietorships, real estate investment trusts (REITs), and regulated investment companies (RICs). If your business is a flow-through, the deduction is simply not available — full stop.
This eligibility cliff drives a recurring conversation in tax planning. A growing software company organized as an S corporation with strong international sales may find that the after-tax economics of converting to a C corporation are surprisingly attractive, even before considering qualified small business stock (QSBS) treatment under Section 1202. The flip side: C corporation conversions trigger their own tax consequences, double taxation on dividends, and entity-level state tax exposure that can swamp the benefit. This is a modeling exercise, not a Reddit-thread decision.
What "Foreign-Derived" Actually Means
Section 250 doesn't simply ask whether the customer is foreign. It applies a two-pronged test that has tripped up countless corporations during audits.
The Foreign Person Test
The buyer must be a foreign person — meaning any individual or entity that is not a U.S. person. Foreign subsidiaries of U.S. companies count as foreign persons. So do unrelated foreign corporations, non-resident individuals, and foreign branches of U.S. financial institutions.
The Foreign Use Test
The income must be derived from property sold for foreign use or services provided to a person or with respect to property outside the United States. "Foreign use" means use, consumption, or disposition outside the U.S. A laptop sold to a German distributor that resells to a German end user qualifies. The same laptop sold to a German distributor that re-exports to a U.S. retailer does not.
The foreign use test gets more nuanced when intangible property or business-to-business services are involved:
- Sales of general property to end users: The foreign use is presumed if the property is delivered outside the U.S. or shipped via a foreign address.
- Sales of general property to non-end users (resellers, distributors): The seller must reasonably establish that the property will ultimately be used outside the U.S.
- Sales or licenses of intangible property: The seller must determine the proportion of revenue attributable to foreign use, often using royalty allocations or end-market data.
- Services to consumers: Provided where the consumer is located.
- Services to businesses: Provided where the business operations or property benefiting from the service are located.
The regulations were significantly relaxed in their final form in 2020. For sales of general property to end users and consumer services, no specific document type is required — taxpayers can rely on "any reasonable method" to substantiate foreign status and foreign use. For business-to-business transactions, intangible property sales, and services tied to property location, the IRS still expects substantiation — typically contracts, invoices, shipping records, customer certifications, and transfer pricing documentation. The documentation must exist by the time the federal return is filed, and contemporaneous records carry significantly more weight than after-the-fact reconstructions.
The Old (Pre-2026) FDII Calculation
Understanding the legacy formula matters because most corporations are still filing returns under it for tax year 2025 (the return filed in 2026). The math has four steps.
Step 1: Calculate Deduction Eligible Income (DEI)
Start with the corporation's gross income, then exclude several specific categories:
- Subpart F income
- GILTI
- Foreign branch income
- Dividends from CFCs
- Domestic oil and gas extraction income
- Financial services income
From the remaining gross income, subtract the deductions properly allocable to it (including a share of interest expense, R&E expense, and general overhead). The result is DEI.
Step 2: Determine Foreign-Derived DEI (FDDEI)
This is the slice of DEI that comes from sales of property to foreign persons for foreign use, or services provided to persons or property outside the U.S.
Step 3: Calculate Deemed Intangible Income (DII)
DII = DEI − (10% × QBAI)
QBAI is the average aggregate adjusted basis of the corporation's tangible depreciable property used in producing DEI. The "10% × QBAI" subtraction is treating a normal return on tangible assets as routine (and therefore not "intangible"-driven).
Step 4: Calculate FDII and the Deduction
FDII = DII × (FDDEI ÷ DEI)
Section 250 Deduction = FDII × 37.5%
Worked Example (Pre-2026)
Assume a domestic C corporation with:
- DEI of $4,000,000
- FDDEI of $3,000,000 (75% of DEI is foreign-derived)
- QBAI of $5,000,000
The math runs:
- DII = $4,000,000 − (10% × $5,000,000) = $3,500,000
- FDII = $3,500,000 × ($3,000,000 ÷ $4,000,000) = $2,625,000
- Section 250 deduction = $2,625,000 × 37.5% = $984,375
At 21%, that deduction is worth $206,719 in federal tax savings for the year.
The New (Post-2025) FDDEI Calculation
OBBBA collapsed the four-step calculation into something much simpler.
Step 1: Calculate DEI
Same as before, with one key change: gain from the sale or other disposition of intangible property and other depreciable/amortizable property is excluded from DEI for dispositions occurring after June 16, 2025. This was designed to prevent corporations from selling appreciated intangibles into the FDDEI bucket to inflate the deduction.
Step 2: Determine FDDEI
Same definition as before — DEI from sales of property to foreign persons for foreign use, or services to persons or property outside the U.S.
Step 3: Calculate the Deduction
FDDEI Deduction = FDDEI × 33.34%
That's it. No QBAI offset. No DII calculation. No FDDEI/DEI ratio multiplication. The export-qualifying portion of DEI is simply multiplied by 33.34%.
Worked Example (Post-2025)
Using the same corporation:
- DEI of $4,000,000
- FDDEI of $3,000,000
Section 250 deduction = $3,000,000 × 33.34% = $1,000,200
At 21%, that's worth $210,042 in federal tax savings.
In this example, the new regime is slightly more generous than the old one — because the QBAI offset previously trimmed $500,000 from the base. Capital-light businesses (software, services, IP licensing) generally benefit from the simplification. Capital-intensive businesses (manufacturers with large depreciable equipment bases) used to get a smaller benefit because of the QBAI subtraction; now that's no longer a drag.
The Interest and R&E Allocation Change Is the Real Story
For tax years beginning after December 31, 2025, taxpayers no longer have to allocate interest expense or R&E expenditures against eligible income. Under the prior regime, this allocation was the single biggest reason FDII benefits got eroded — pharmaceutical companies running massive R&D programs and leveraged buyouts servicing acquisition debt routinely lost 30% to 80% of their notional FDII benefit to expense allocation. Eliminating the allocation requirement is, for many large corporations, more valuable than the rate cut would otherwise suggest.
The Taxable Income Limitation Trap
Both the old and new regimes contain a critical limitation that catches startups and recently profitable corporations off guard.
The combined FDII + GILTI deduction (or FDDEI + NCTI deduction) cannot exceed the corporation's taxable income for the year (computed without regard to the Section 250 deduction itself). If the sum of FDII and GILTI exceeds taxable income, the excess proportionally reduces both buckets.
In practical terms: if your corporation has $5 million of FDDEI but only $3 million of total taxable income (because of NOLs, large deductions, or losses in other lines of business), your deduction base gets capped at $3 million. The Section 250 deduction does not generate or increase a net operating loss. It is strictly a deduction against current-year taxable income.
This makes timing matter. Corporations expecting a major loss year (large impairment, restructuring charge, or NOL utilization) may want to defer discretionary deductions or accelerate FDDEI revenue recognition to maximize the benefit. Corporations expecting a strong taxable income year should consider whether to push qualifying export revenue into that year's reporting if reasonable methods exist.
Five Common Mistakes That Erase the Deduction
The IRS has been auditing FDII claims aggressively since 2020, when the final regulations were issued. Five recurring failure patterns drive most adjustments.
1. Misclassifying "Foreign Use"
The single most common error is treating any sale to a foreign customer as automatically qualifying. A U.S. distributor that buys hardware from a domestic manufacturer and resells it to a foreign affiliate may not generate FDDEI for the manufacturer if there's no documented foreign use at the end of the chain. Conversely, services provided inside the U.S. can qualify for FDDEI if they benefit a foreign business operation — a fact pattern that many corporations never investigate.
2. Sloppy Expense Allocation
Under the pre-2026 regime, every deduction had to be allocated and apportioned between gross DEI and other income classes using the Section 861 regulations. Corporations that simply allocated based on gross income ratios (instead of stewardship vs. supportive function vs. directly traceable categories) often over-allocated expenses to DEI, deflating the deduction. Under the post-2025 regime, interest and R&E are no longer allocated, but other operating expenses still are. The allocation work isn't optional.
3. Failing the Foreign Person Documentation
For business-to-business sales, taxpayers must substantiate that the customer is a foreign person. Customer self-certifications, articles of incorporation, foreign tax identification numbers, and W-8 forms are typical evidence. Corporations that cannot produce this documentation during an exam often see the deduction reduced or denied for entire customer accounts.
4. Treating Intercompany Transactions Carelessly
Sales to a controlled foreign corporation (CFC) can qualify as FDDEI, but only if the property is ultimately used or sold outside the U.S. by the CFC. Round-tripping — where a U.S. parent sells to its foreign subsidiary, which then re-sells back into the U.S. — does not qualify and triggers an "anti-abuse" reading by examiners. Transfer pricing documentation must align with FDDEI documentation; inconsistencies are a red flag.
5. Forgetting to File Form 8993
Some corporations claim the Section 250 deduction on the Form 1120 but never attach Form 8993. The deduction is technically not allowed without the form. This is an easy fix on amended returns within the statute of limitations, but it's a recurring oversight.
Who Benefits Most in 2026
The OBBBA changes shift the value distribution. The new regime tends to favor:
- Pure software and SaaS companies with foreign customer revenue — capital-light businesses gain from QBAI elimination, and the simpler formula reduces compliance cost.
- Pharmaceutical and biotech exporters with significant R&E spending — the elimination of R&E allocation is a major benefit.
- Patent and technology licensors receiving royalties from foreign affiliates — the simpler formula and clearer documentation rules reduce audit risk.
- Leveraged corporate exporters carrying significant debt — the elimination of interest allocation can dramatically expand the deduction.
- Service businesses providing engineering, consulting, or design services to foreign businesses or with respect to foreign-located property — clearer foreign use determination and no QBAI drag.
The new regime is somewhat less favorable to highly capital-intensive U.S. manufacturers that previously had a large QBAI cushion to absorb the 10% deemed routine return. But the rate cut and elimination of expense allocations usually produce a net positive even for them.
What to Do Before Year End
For corporations with December 31 fiscal year ends, the choices made in the next several months will shape both the 2025 (filed 2026) and 2026 (filed 2027) Section 250 deductions.
Action items for the 2025 return:
- Build the four-step calculation under the legacy regime. Don't try to skip steps.
- Review expense allocation methodology for interest and R&E — this is where most legacy-regime money is made or lost.
- Pull contracts, shipping records, and customer certifications for every account included in FDDEI. Build the file before the return is filed.
- Compute the taxable income limitation. If it bites, consider whether discretionary deductions can be deferred.
Action items for the 2026 return:
- Update accounting models, internal calculation spreadsheets, and tax provision templates to reflect the new 33.34% rate, the elimination of QBAI, and the elimination of interest/R&E allocation.
- Re-evaluate transfer pricing arrangements. The simpler FDDEI calculation makes some structures more attractive (direct sales from U.S. to foreign customers) and others less so (multi-tier IP holding company structures designed around the old QBAI mechanics).
- Review intangible property dispositions planned for 2026. Sales of intangibles or depreciable property no longer count toward DEI, so post-acquisition restructurings should be sequenced carefully.
- Document foreign use methodology in a written policy. Auditors increasingly expect a contemporaneous, board-approved methodology — not just transactional evidence.
State Tax Coordination
Most states do not conform to Section 250 in full. Approximately 20 states fully or partially decouple from the FDDEI deduction, meaning the federal deduction is added back at the state level. A handful conform fully, and a small number have unique modifications. Multistate corporations need to model the interaction between FDDEI and state apportionment formulas — what looks like a 7-percentage-point federal benefit can shrink to 4 or 5 points after state add-backs.
This is a recurring bookkeeping and accounting challenge. Tracking which expense allocations apply for federal versus state purposes, and reconciling apportionment across multiple jurisdictions, requires careful general ledger discipline. Corporations that try to retrofit this analysis at year-end typically discover gaps that are expensive to fill.
Keep Your Cross-Border Books Audit-Ready
The Section 250 deduction can save a mid-sized C corporation hundreds of thousands of dollars a year — but only if the underlying records hold up to IRS scrutiny. Foreign use determinations, expense allocations, transfer pricing documentation, and customer status certifications all sit on top of the corporation's general ledger and revenue accounting systems. When the books are messy, the deduction becomes vulnerable.
Beancount.io provides plain-text accounting that gives you complete transparency and version control over your financial data, making it far easier to trace foreign-derived revenue, allocate expenses across DEI buckets, and reconcile transfer pricing entries across entities. No black boxes, no vendor lock-in, and AI-ready data that integrates cleanly with whatever tax provision software your CPA uses. Get started for free and see why developers and finance professionals are switching to plain-text accounting.