R&D Tax Credit: Do You Qualify? The Four-Part Test

Many businesses qualify for the R&D tax credit without realizing it. Under IRC Section 41, your business qualifies if its research activities meet a four-part test: the work must serve a permitted purpose, rely on a technological discipline, aim to eliminate uncertainty, and use a genuine process of experimentation. The credit is worth up to 20% of qualified research expenses above a base amount, and it applies to a wide range of industries, from software development and manufacturing to food production and engineering services.

What Is the R&D Tax Credit?

The federal R&D tax credit, formally the Credit for Increasing Research Activities, is a dollar-for-dollar reduction of federal income tax liability for businesses that incur qualified research expenses. Congress created it in 1981 to encourage domestic innovation, and it has been a permanent feature of the tax code since the PATH Act of 2015.

The credit is governed by IRC Section 41 and sits alongside, but is separate from, the Section 174 (now Section 174A) deduction for research and experimental expenditures. The OBBBA, signed July 4, 2025, restored immediate expensing for domestic R&E costs under a new Section 174A, effective for tax years beginning after December 31, 2024. The Section 41 credit continues to operate independently, though there is an important interaction between the two provisions discussed below.

The Section 41 Four-Part Test

To generate the R&D tax credit, each qualifying activity must satisfy all four prongs of the Section 41 test. A single failed prong disqualifies that activity. Here is what each prong requires.

1. Permitted Purpose

The research must aim to create or improve a “business component,” which includes a product, process, formula, invention, technique, or software used in your trade or business. The improvement must relate to the business component’s performance, reliability, quality, or function. Market research, customer preference studies, and efficiency improvements that do not involve technical development are not qualifying purposes.

2. Technological in Nature

The activity must fundamentally rely on principles of engineering, computer science, biological science, or physical science. Social sciences, economics, behavioral science, and the arts do not count. This prong is broadly satisfied by most software development, product engineering, and manufacturing process work, as long as the effort draws on a hard-science discipline.

3. Elimination of Uncertainty

Your company must be trying to eliminate technical uncertainty about the capability or method needed to develop or improve the business component. Importantly, the uncertainty does not need to be new to the world, only new to your company. If your engineering team is genuinely unsure whether a particular design approach will work, that is enough to satisfy this prong.

4. Process of Experimentation

The work must involve a systematic process of evaluating alternatives to address the technical uncertainty. This means testing hypotheses, modeling, simulation, or iterative design review. Simple trial-and-error or ad hoc troubleshooting generally does not satisfy this prong. The IRS looks for evidence that the company methodically tested and evaluated different approaches.

Who Qualifies? Industries That Commonly Claim the Credit

The credit is not limited to pharmaceutical companies or corporate research labs. Any business spending money on activities that satisfy the four-part test is a potential claimant. Common qualifying industries include:

• Software and technology: Custom software development, cloud application architecture, API integrations, machine learning model development.
• Manufacturing and engineering: Designing new or improved products, tooling, manufacturing processes, or materials.
• Life sciences: Drug development, medical device design, clinical research conducted by the taxpayer.
• Construction and architecture: Developing proprietary structural systems, energy-efficient building techniques, or novel construction methods.
• Food and beverage: Formulating new products, improving shelf life, or developing new processing techniques.
• Aerospace and defense: Systems engineering, component testing, new propulsion or materials research.

A useful first question is: does your team spend time solving technical problems where the answer is not obvious? If yes, you likely have qualifying activity worth examining.

What Expenses Count? Qualified Research Expenses (QREs)

Once you confirm that an activity qualifies, you need to identify the associated qualified research expenses. Under Section 41, QREs fall into three categories.

Wages

Wages paid to employees for performing, directly supervising, or directly supporting qualified research are QREs. For this purpose, “wages” means taxable wages under Section 3401(a), which is generally the amount in Box 1 of Form W-2. That figure includes salary, bonuses, and taxable stock option exercises, but not nontaxable fringe benefits, 401(k) matches, or health premiums paid under a cafeteria plan. Only the portion of an employee’s time attributable to qualified research counts. A software engineer who spends 60% of their time on qualifying development projects contributes 60% of their wages to QREs.

Supplies

Tangible property consumed in the conduct of qualified research qualifies. This includes raw materials used in prototypes, lab consumables, and test materials. It does not include capital equipment or property that is not consumed.

Contract Research

65% of amounts paid to third-party contractors for qualified research counts as a QRE, provided the taxpayer retains the rights to the research results and bears the financial risk of failure. If the contract shifts both the risk and the rights to the contractor, the research is “funded research” and the taxpayer cannot claim it. Amounts paid to a qualified research consortium increase to 75%.

Cloud Computing Costs

Amounts paid for the right to use computers, including cloud computing resources used directly in qualified research, are expressly included in in-house research expenses under Section 41(b)(2)(B). This has become increasingly significant as development environments move to cloud platforms.

Two Ways to Calculate the Credit

Taxpayers choose between the regular credit and the Alternative Simplified Credit (ASC). Most businesses claiming the credit for the first time use the ASC because it avoids the complex historical base-period calculation.

Regular Credit (20%)

The regular credit equals 20% of current-year QREs above a base amount. The base amount is calculated using a fixed-base percentage, which is the ratio of the company’s historical QREs to gross receipts during 1984 to 1988, multiplied by current-year gross receipts. The minimum base is 50% of current-year QREs. Businesses without 1984 to 1988 data use a startup calculation.

Alternative Simplified Credit (ASC) (14%)

The ASC equals 14% of current-year QREs above 50% of the average QREs for the three preceding tax years. For businesses with no QREs in those three years, the credit is 6% of current-year QREs. Because the ASC uses recent history rather than 1984 to 1988 data, it is simpler to compute and the election is made annually on Form 6765.

Note that the effective credit rate is lower than the headline percentages once the base-amount reduction is applied. The Congressional Research Service has estimated the effective average rate for marginal R&D investments at approximately 8.2% (an industry-average estimate, not a statutory figure).

Startup and Small Business Provisions

Eligible small businesses can elect to apply the R&D credit against payroll tax instead of income tax. This is particularly valuable for early-stage companies with losses that cannot use an income tax offset.

To qualify for the payroll tax election, a business must:

• Have gross receipts of $5 million or less for the credit year, and
• Have had no gross receipts in any tax year more than 5 years before the credit year.

The maximum payroll tax offset is $500,000 per year, a cap the Inflation Reduction Act raised from $250,000 effective for tax years beginning after December 31, 2022. The credit applies first against the employer’s 6.2% Social Security share and then against the employer’s 1.45% Medicare share once the Social Security portion is exhausted. The election is made in Section D of Form 6765 on a timely filed original return (it cannot be made on an amended return), and the credit is claimed against payroll taxes on Form 941.

Section 174A Interaction: Expensing vs. the Credit

Before OBBBA, the most painful planning issue in R&D tax was the TCJA-era requirement to amortize domestic R&E costs over 5 years rather than expense them immediately. OBBBA fixed this by enacting Section 174A, which restores immediate expensing for domestic R&E costs for tax years beginning after December 31, 2024. Foreign R&E costs continue to be amortized over 15 years.

The interaction with the Section 41 credit runs through Section 280C(c). By default, a taxpayer claiming the R&D credit must reduce their Section 174A deduction by the amount of the credit. Alternatively, the taxpayer can elect to take a reduced credit (the credit multiplied by 1 minus the top corporate tax rate, currently 21%), allowing the full 174A deduction to stand. For most profitable C-corporations, the 280C(c) election is mathematically neutral; for pass-through entities the comparison requires case-by-case analysis.

For businesses with unamortized 2022 to 2024 domestic R&E balances, OBBBA provided transition options: deduct the full remaining balance in 2025, or spread it across 2025 and 2026. Small businesses (average annual gross receipts of $31 million or less) had a window through July 6, 2026, to amend prior returns and apply immediate expensing retroactively.

Activities That Do Not Qualify

Certain activities are expressly excluded under Section 41(d)(4), regardless of how technical or expensive they are:

• Research conducted after commercial production begins on that component.
• Adaptation of an existing business component to a particular customer’s requirements (unless the adaptation itself involves qualifying technical uncertainty).
• Duplication of an existing component.
• Surveys, studies, and market research.
• Internal use software that does not clear the high-threshold-of-innovation test.
• Research conducted outside the United States.
• Research in the social sciences, arts, or humanities.
• Funded research where another party bears financial risk and retains rights to results.

The funded-research exclusion is a common audit trigger. If a customer contract states that your company is responsible for specific deliverables and the customer retains IP rights, the IRS may characterize the work as funded research and disallow the credit on those activities.

Documentation: The New Form 6765 Section G Requirement

The IRS finalized updated Form 6765 instructions in February 2026. For tax years beginning in 2026, Section G of Form 6765 is mandatory for most filers. Section G requires taxpayers to itemize QREs by business component in descending order of cost until they reach 80% of total QREs or 50 components, whichever comes first. Wages must be broken out into direct research, supervision, and support categories.

Two exemptions from Section G apply. Businesses with QREs at or below $1.5 million and average annual gross receipts for the prior three years at or below $50 million (measured at the controlled-group level) are not required to complete Section G. Qualified small businesses electing the reduced payroll tax credit under Section 41(h) are also exempt. Note an important exception: any amended return or administrative adjustment request that claims the R&D credit must complete Section G regardless of these exemptions. Section E, which discloses the total number of business components and the amount of officer wages included in QREs, is required for all filers.

The practical implication is that contemporaneous documentation of which employees spent time on which projects, what supplies were used, and who contracted work is now more important than ever. Retroactive reconstruction based on estimates carries significant audit risk.

How to Claim the Credit

File Form 6765 with your federal income tax return (Form 1120 for corporations, Form 1065 for partnerships, or Form 1040 Schedule for S-corps and sole proprietors). The credit flows through to individual owners on Schedule K-1 for pass-throughs. Unused credit can be carried back 1 year and forward 20 years.

If you missed the credit in prior years, you can generally amend returns within the standard 3-year statute of limitations. For payroll tax credits, the election must be made on a timely filed return, including extensions.

Working with a qualified tax advisor who can structure your business component documentation before year-end is the most effective way to maximize and defend the credit. Modus’s tax advisory practice works with mid-market companies to identify qualifying R&D activities and build documentation frameworks that hold up under IRS review. Our advisory team can also help coordinate the interaction between the Section 41 credit and your Section 174A expensing strategy.

Related reading: QBI Deduction Explained: How Pass-Through Businesses Claim 20%

Frequently Asked Questions

Does my business have to be in a tech industry to qualify for the R&D tax credit?

No. The R&D tax credit is industry-neutral. Manufacturers, food producers, engineering firms, construction companies, and many service businesses incur qualifying research expenses. The key question is whether your team is systematically solving technical problems, not which industry you are in.

Can I claim the R&D tax credit and also deduct R&D expenses under Section 174A?

Yes, but there is an interaction under Section 280C(c). By default, your Section 174A deduction is reduced by the amount of the credit. You can elect a reduced credit rate instead, which lets you keep the full deduction. Your tax advisor should model both options given your entity type and effective tax rate.

What is the difference between the regular credit and the Alternative Simplified Credit?

The regular credit is 20% of QREs above a base amount tied to your 1984 to 1988 historical research ratio. The ASC is 14% of QREs above 50% of your average QREs for the three preceding years. The ASC is simpler for most businesses and avoids the need to reconstruct decades-old financial data.

Can startups use the R&D tax credit even if they have no income tax liability?

Yes. Qualifying small businesses with gross receipts under $5 million and fewer than 6 years of gross receipts history can elect to apply up to $500,000 per year of the credit against the employer’s share of Social Security payroll taxes, providing a cash benefit even in a loss year.

What is “funded research” and why does it matter?

Funded research is research paid for by another party under a contract where that party bears the financial risk and retains the rights to the results. If your work is funded research, you cannot claim the Section 41 credit on those activities, even if the work otherwise meets the four-part test. This exclusion applies whether the funding comes from a commercial customer or a government agency.

How does the new Form 6765 Section G requirement change what businesses need to track?

Starting with tax years beginning in 2026, most filers must report QREs at the business-component level, broken out by direct research wages, supervisory wages, support wages, supplies, and contract research, covering components that together represent at least 80% of total QREs. This makes real-time project-level time tracking and expense allocation essential. Businesses that relied on high-level estimates in prior years should update their tracking systems before the tax year closes.