Professional firm limits on QBI
Architecture and engineering are not specified service trades, so owners keep the 20% QBI deduction above the income threshold, subject to the wage and property limits. Many owners do not know this.
Industry tax guide
Architecture and engineering tax and accounting
Tax credits for the design work your firm already does, and reporting that shows which projects make money.
Architecture and engineering firms sell expertise by the hour or the project, carry unbilled work for months, and solve technical problems on every job. Profit depends on how well fees cover the time a project really takes.
Much of that problem-solving can qualify for the research credit, and energy-efficient designs for public and nonprofit owners have supported the 179D deduction. Both need project-level documentation that most firms already keep in some form.
Compared with a general business
What makes taxes different for architecture and engineering
Revenue on long projects
Fees billed by phase, retainage and unbilled work in progress make the cash and accrual pictures diverge, and the accounting method choice changes taxable income.
Research performed under client contracts
Whether design work counts as qualified research depends on contract terms, which is unusual: the same work can qualify on one project and not on another.
Licensing in many states
Firms licensed in several states often have income and payroll filing obligations wherever their engineers work or their projects sit.
The rules in detail
Tax rules for architecture and engineering
R&D credit for design work
Developing new structural systems, mechanical designs or building performance models can be qualified research. The key test for a design firm is whether the contract leaves the firm at financial risk for failure and gives it substantial rights to the work; research fully paid for regardless of outcome is excluded as funded research.
179D for projects that began by June 30, 2026
Government, tribal and nonprofit owners can allocate the energy efficient commercial buildings deduction to the designer. The 2025 tax law ended 179D for buildings whose construction begins after June 30, 2026, but projects that started by then can still be claimed when placed in service, using Form 7205.
Research costs are deductible again
Domestic research and experimental costs paid in tax years starting in 2025 can be deducted right away under Section 174A. Firms with average gross receipts of $31 million or less can also apply the change to 2022 through 2024.
Planning moves
Ways to save tax in architecture and engineering
Claim the R&D credit on design work
Projects with fixed fees and retained rights are reviewed for qualified research every year.
Use the payroll tax offset
Firms with under $5 million in gross receipts and five or fewer years of receipts can apply up to $500,000 a year against payroll taxes.
Collect remaining 179D allocations
Public and nonprofit buildings that began construction by June 30, 2026 can still be allocated when placed in service.
Keep the QBI deduction
Owner salary and entity structure are set so the deduction is not lost to the wage limit.
Choose the cash or accrual method deliberately
Firms under the gross receipts test can often use the cash method and defer tax on unbilled and uncollected fees.
Fund a retirement plan for partners
A 401(k) with profit sharing, or a cash balance plan for older partners, shelters high professional income.
Working with OICPA
How we help
Claim the research credit on design projects
We review contracts for risk and rights, identify qualifying projects and build the time-based support an examiner will ask for.
R&D Tax CreditCollect 179D allocations still in the pipeline
List public and nonprofit projects that began before July 2026 and request the allocation letters before the buildings are placed in service.
Business Tax AdvisoryEstimate the credit first
See what the alternative simplified credit could be worth from your wage and contractor data before a full study.
R&D Tax Credit EstimatorProject profitability you can act on
Work-in-progress and project margin reports that show which clients and contract types earn their fee.
Management Reporting & KPI DashboardsBookkeeping and reporting
The accounting behind the tax work
Review project margins and partner compensation together; organize technical project records if a specialist incentive review is appropriate.
The operating challenge
Unbilled time, project revisions, and subcontractor costs can erode a profitable-looking engagement before the loss becomes visible in monthly reports.
The records that matter
Project budgets, time records, billing schedules, subcontractor costs, and ownership agreements give the review a practical starting point. We identify missing information before recommending changes.
What you can expect
- A prioritized review of the industry-specific accounting issues above
- A tailored reporting and document checklist based on your operating records
- An agreed action plan connecting financial reporting, tax deadlines, and specialist coordination
Frequently asked questions
Does a fixed-fee contract help the R&D credit?
Usually. Under a fixed fee the firm bears the cost if the design takes longer, which supports the financial risk test. Time-and-materials contracts paid regardless of outcome are more often treated as funded research.
Can we still get 179D allocations?
Yes, for public, tribal and nonprofit buildings whose construction began on or before June 30, 2026. The deduction is claimed for the year the building is placed in service, so some of these projects are still ahead of you.
Can a small firm use the credit against payroll tax?
A qualified small business, generally one with under $5 million in gross receipts and no receipts more than five years back, can apply up to $500,000 a year of the research credit against payroll taxes.
Related articles
References
- 26 U.S. Code § 41: Credit for increasing research activitiesLegal Information Institute, Cornell Law School
- 26 U.S. Code § 174A: Domestic research or experimental expendituresLegal Information Institute, Cornell Law School
- 26 U.S. Code § 179D: Energy efficient commercial buildings deductionLegal Information Institute, Cornell Law School
- About Form 7205, Energy Efficient Commercial Buildings DeductionInternal Revenue Service
Rules reflect federal tax law as of November 2026.