Tax Planning for Architecture and Engineering Firms: SSTB Classification, Project Accounting, and Entity Structure
Architecture and engineering are carved out of the SSTB definition in IRC 199A(d)(2), which applies the service list without regard to the words “engineering, architecture”, so firm principals earning above the income thresholds keep the QBI deduction, subject to the W-2 wage and property limits. An architecture firm partner earning $600,000 in qualified business income can claim up to a $120,000 QBI deduction (20%) if the firm’s W-2 wages and property support it. Engineering firms get the same treatment.
A&E firm tax planning priorities:
| Strategy | Annual Tax Savings | Notes |
|---|---|---|
| S-Corp election | Varies | Payroll tax saved vs. QBI deduction lost on salary |
| 401(k) + profit sharing | $17,400-$25,900 | Standard |
| Cash balance/defined benefit plan | $55,500-$148,000 | Age-dependent |
| Cash method timing | Varies | Control billing/collection timing |
| PTET election | $10,000-$40,000 | High-tax state firms |
| Equipment depreciation | Up to 37% of purchase | Major equipment purchases |
SSTB classification for A&E activities:
| Activity | SSTB? | QBI Eligible? |
|---|---|---|
| Architectural design services | No | Yes (wage and property limits above threshold) |
| Structural engineering | No | Yes (wage and property limits above threshold) |
| Civil engineering | No | Yes (wage and property limits above threshold) |
| MEP (mechanical, electrical, plumbing) design | No | Yes (wage and property limits above threshold) |
| Construction management (non-licensed) | Possibly no | Possibly yes |
| Environmental testing/remediation | Possibly no | Possibly yes |
| Land surveying (non-engineering state) | Possibly no | Possibly yes |
| Geotechnical testing | Possibly no | Possibly yes |
| 3D scanning/BIM services (non-licensed staff) | Possibly no | Possibly yes |
A&E equipment depreciation:
| Equipment | Typical Cost | MACRS Life | Year 1 Deduction |
|---|---|---|---|
| Large format plotter/printer | $10,000-$30,000 | 5 years | 100% |
| 3D printer (professional grade) | $20,000-$100,000 | 5-7 years | 100% |
| Survey equipment (total stations, GPS) | $15,000-$50,000 | 5-7 years | 100% |
| Drones (surveying, inspection) | $5,000-$30,000 | 5 years | 100% |
| Workstations (CAD/BIM capable) | $5,000-$15,000 each | 5 years | 100% |
| Software (AutoCAD, Revit, licenses) | $5,000-$50,000/year | 3-5 years or expense | Deductible |
| Vehicles (field work, over 6,000 lbs) | $50,000-$80,000 | 5 years | 100% |
| Office buildout (QIP) | $100,000-$500,000 | 15 years | 100% (bonus) |
How do architecture and engineering firms minimize taxes?
How do staff engineers affect a principal’s S-Corp salary?
They’re part of the picture the IRS uses. Its guidance says the key to reasonable compensation is what the shareholder did for the company, found by looking at where gross receipts came from: the shareholder’s own services, non-shareholder employees, or capital and equipment. In a firm paying $1.6 million to staff engineers and drafters, some receipts trace to that staff.
Courts also weigh what the firm pays its non-shareholder employees, along with the principal’s training and experience, duties, hours, and what comparable businesses pay for similar services. There’s no formula, since the Code and regulations have no specific guideline, and if a principal’s salary is too low the IRS can reclassify distributions as wages.
Salary also feeds the QBI math. It isn’t qualified business income, but above the threshold ($394,600 joint for 2025, $403,500 for 2026) the deduction is capped by W-2 wages, and a principal’s own salary should count toward them (an inference, since officers are employees). From 2026 the phase-in above that threshold is $150,000 wide for joint filers, for the wage limit and any SSTB phase-out.
What entity structure works best for a business with multiple owners?
A multi-member LLC taxed as a partnership is the most flexible default. It files Form 1065 and issues K-1s to each member, with the operating agreement controlling profit allocation, voting rights, and buyout terms. An S-Corp works if all owners are US individuals (no entity or foreign owners), the business has no more than 100 shareholders, and everyone agrees on equal-class stock. A C-Corp is necessary if you want venture capital (preferred stock classes), have foreign owners, or plan to retain significant earnings at the 21% corporate rate. LLCs offer the most flexibility for unequal profit splits, special allocations, and varying capital contributions.
Related guides:
- Consulting Business Entity Structure: LLC vs S-Corp and the SSTB Problem
- Event Planning Business Entity Structure: LLC, S-Corp, and the SSTB Question
- Law Firm Entity Structure: PC, PLLC, LLP, and Why the S-Corp Election Matters
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Yarik Yarosh, CPA. "Tax Planning for Architecture and Engineering Firms: SSTB Classification, Project Accounting, and Entity Structure." Blue Cloud CPA, September 5, 2026, updated September 23, 2026. https://bluecloudcpa.com/guides/small-business-tax-planning-architecture-engineering-firms-sstb
This guide is general information, not tax advice for your specific situation. Which points apply, and how, depends on your facts.