Research and Development Investment: Credit, Payroll Election, and Section 174A

The federal R&D tax credit lets a business reduce its income tax by up to 20% of the qualified research spending that exceeds a calculated base amount, or 14% under a simpler alternative method. It is claimed on Form 6765 with the company’s income tax return, and each research project must pass a four-part test to count.¹ The credit sits in Section 41 of the tax code and is separate from the Section 174A deduction that lets you write off domestic research costs in the year you spend them.² Most companies claim both.

What Counts as Qualified Research

Every project you claim has to satisfy all four of the following tests. Failing any one disqualifies the whole project, and IRS examiners look for exactly that during audits.

The spending must be a research or experimental expenditure connected to your trade or business, the same threshold used for Section 174.
The research must seek information that is technological in nature, meaning it relies on engineering, physical science, biological science, or computer science. Work in social sciences, economics, arts, or humanities is out.¹
The work must aim to develop a new or improved business component — a product, process, software, technique, formula, or invention — with the improvement tied to function, performance, reliability, or quality. Changes driven by style, taste, or seasonal design don’t qualify.³
Substantially all of the activity must be a process of experimentation evaluating alternatives to resolve technical uncertainty that existed at the start of the work.³

The uncertainty prong is where most claims collapse. “We didn’t know which color customers would prefer” is not technical uncertainty. The company has to genuinely not know whether a material will hold up at a given temperature, whether an algorithm can process data at the required speed, or whether a compound will produce the intended reaction. If the answer was already sitting in standard industry knowledge or published research, there was nothing to resolve.

Activities That Don’t Qualify

The statute pulls a long list of work out of the credit even when it looks innovative on the surface.

Research after commercial production begins. Once the product is ready for sale or use, tooling up, trial runs, troubleshooting production equipment, and debugging a finished product are all excluded.³
Adapting an existing product to a specific customer’s needs, even if it takes real engineering.
Duplicating an existing product by reverse-engineering from blueprints, specifications, or a physical sample.
Surveys, market research, advertising, routine data collection, routine quality-control testing, efficiency studies, and management-technique development.¹
Research conducted outside the United States, Puerto Rico, or U.S. possessions.
Research funded by another party through a grant or contract, to the extent of that funding.

Software written primarily for a company’s own internal use faces a higher bar and generally has to clear additional tests beyond the standard four. Software embedded in a qualified production process or sold to customers is treated like any other business component.³

Which Expenses You Can Include

Three categories of spending feed the credit calculation, and misclassifying them is a common audit finding.

Wages are the largest piece of most claims. They cover compensation to employees who directly perform, directly supervise, or directly support qualified research, and the wages have to be subject to federal income tax withholding.¹ “Direct support” is narrower than it sounds. A lab technician preparing samples or an IT staffer configuring a test environment counts; an administrative assistant or payroll clerk does not.

Supplies means tangible items consumed or used during the research, such as chemicals, raw materials, or prototype components. Land, building improvements, and depreciable property like lab equipment are excluded. A beaker that shatters during an experiment qualifies. The bench it sat on does not.¹

Contract research covers payments to outside parties performing qualified research on your behalf. Only 65% of those payments count toward the credit.¹

How the Credit Is Calculated

The credit is incremental. It rewards you for increasing research spending over a historical baseline, not for the total you spend. You pick one of two methods.

Regular Credit

The regular credit is 20% of the current-year qualified research expenses that exceed your base amount. The base amount is your fixed-base percentage multiplied by your average gross receipts over the four preceding years, and the fixed-base percentage itself is drawn from your historical ratio of research spending to gross receipts.⁴ Companies with long operating histories often find this method data-intensive.

Alternative Simplified Credit

Most companies use the alternative simplified credit because it needs less historical data. It equals 14% of current-year qualified research expenses that exceed 50% of your average qualified research expenses over the three prior tax years.¹ If you had no qualifying expenses in any of those three prior years, the rate drops to 6% of current-year expenses. Once elected, the ASC keeps applying every year until you revoke it on a timely filed original return for a later year.⁵

Whichever method you choose, the credit reduces tax dollar for dollar. It also reduces the deduction you can take for the same R&D expenses. You can elect a reduced credit under Section 280C to sidestep that adjustment; the math is cleaner but the credit is smaller.

Payroll Tax Election for Startups

Early-stage companies often generate credits but owe little income tax. Section 41(h) lets a qualified small business apply up to $500,000 of its R&D credit each year against payroll taxes instead of letting the credit sit as a carryforward.⁶

You qualify if your gross receipts for the current tax year are under $5 million and you had no gross receipts at all in any year before the five-year period ending with the current year.¹ In practice that means the company is about five years old or younger and still small. Tax-exempt organizations don’t qualify.

The credit first offsets the employer share of Social Security tax, capped at $250,000 per quarter. Any leftover applies against the employer share of Medicare tax. Anything still unused rolls to the next quarter.⁶

How to File and Document the Claim

The credit is claimed on Form 6765, attached to the income tax return. Section A handles the regular credit and Section B handles the ASC. You complete one or the other, not both.⁵

For tax years beginning after 2025, Section G of Form 6765 requires detailed business component information. You have to identify each business component you’re claiming expenses for, using identifiers consistent with your own internal records.⁵ Vague department-wide estimates won’t cut it. The IRS expects project-level documentation.

Amended-return claims face additional hurdles. The filing has to include specific information to be considered valid, and if you submit a credit study, you have to point to the exact pages that contain the required details. If you’re using statistical sampling to estimate qualified expenses, know that the IRS does not treat acceptance of Form 6765 as approval of your sampling methodology.⁵

Keep records as the work happens. Project logs, time-tracking data, lab notebooks, email threads describing technical problems, and meeting notes describing design alternatives all serve as evidence that the four-part test was met. Companies that wait until filing season to reconstruct their documentation consistently struggle in audit.

The Section 174A Deduction Is Separate

The credit is not the deduction, and mixing them up costs money. Section 174A, enacted by the One Big Beautiful Bill Act, permanently restores immediate expensing for domestic research and experimental expenditures paid or incurred in tax years beginning after December 31, 2024, reversing the five-year capitalization the Tax Cuts and Jobs Act had imposed starting in 2022. Software development costs are explicitly included.² A company can instead elect to capitalize and amortize domestic R&D over at least 60 months from the month it first benefits from the research, which may help if current-year losses would otherwise waste the deduction.

Foreign research is treated less generously. R&D attributable to activity outside the United States must be capitalized and amortized over 15 years, beginning at the midpoint of the tax year the costs were paid or incurred.⁷ A company spending $2 million a year on overseas lab work can deduct only about $133,000 of that annually; the same spending at a domestic facility would be fully deductible in year one. That foreign research also cannot generate the Section 41 credit, and neither can work paid for by someone else through a grant or contract.¹

State treatment varies. Some states follow the federal rules, others kept their own amortization schedules or allow separate elections, and a company operating across state lines should check each state’s conformity position before assuming the federal answer carries over.

1
Office of the Law Revision Counsel. 26 USC 41 – Credit for Increasing Research Activities
2
Office of the Law Revision Counsel. 26 USC 174A – Domestic Research or Experimental Expenditures
3
Internal Revenue Service. Audit Techniques Guide: Credit for Increasing Research Activities – Qualified Research Activities
4
Internal Revenue Service. Audit Techniques Guide: Credit for Increasing Research Activities – Research Credit Computation
5
Internal Revenue Service. Instructions for Form 6765 (12/2025)
6
Internal Revenue Service. Qualified Small Business Payroll Tax Credit for Increasing Research Activities
7
Office of the Law Revision Counsel. 26 USC 174 – Amortization of Research and Experimental Expenditures