PSC R424: Support – Professional: Expert Witness
R424 is the product and service code (PSC) federal agencies use for “Support – Professional: Expert Witness”, in the “Professional Services” group. Here are the contracts open under it now, the NAICS codes it pairs with, and who buys and wins this work.
- Open contracts now
- 1
- Federal contract spending, FY2025
- $183.3 million
- Share of contract dollars to small businesses, since FY2024
- 27%
Open count as of Nov 7, 2026, 1:18 AM ET. The search counts live, so its total can differ by a notice or two.
Where R424 sits in the PSC Manual
- Category: Service
- Group R: Support SVCS (Prof, Admin, MGMT)
- Group R4: Professional Services
- Code R424: Support – Professional: Expert Witness
NAICS codes used with PSC R424
The NAICS code on a contract sets the size standard for who counts as small. These are the codes agencies pair with R424 most often:
| NAICS | Industry | Spent, last 3 years | Open with PSC R424 |
|---|---|---|---|
| 541199 | All Other Legal Services | $246.9 million | — |
| 541990 | All Other Professional, Scientific, and Technical Services | $100 million | — |
| 541690 | Other Scientific and Technical Consulting Services | $85.9 million | — |
| 541611 | Administrative Management and General Management Consulting Services | $73.1 million | — |
| 541330 | Engineering Services | $64.5 million | — |
| 541618 | Other Management Consulting Services | $34.4 million | — |
| 621111 | Offices of Physicians (except Mental Health Specialists) | — | 1 |
Open contracts under each code, with any PSC: NAICS 541199 · NAICS 541990 · NAICS 541690 · NAICS 541611 · NAICS 541330 · NAICS 541618 · NAICS 621111
Who buys under PSC R424
Agencies with the most contract dollars under R424 over the last three fiscal years, per USAspending.gov. Each name links to that agency's open contracts and buying history:
| Agency | Obligated |
|---|---|
| Offices, Boards and Divisions | $246 million |
| Internal Revenue Service | $202.6 million |
| Federal Trade Commission | $58.9 million |
| Department of the Air Force | $56.8 million |
| Securities and Exchange Commission | $35.5 million |
| Health Resources and Services Administration | $14.8 million |
| Department of the Navy | $14 million |
| Social Security Administration | $9 million |
Federal spending under PSC R424 by year
| Fiscal year | Contract obligations |
|---|---|
| FY2024 | $301.7 million |
| FY2025 | $183.3 million |
| FY2026 (incomplete) | $181 million |
Headline figures use FY2025, the last complete year. FY2026 is still incomplete and will rise until about early January 2027 as Defense data arrives: USAspending.gov publishes Defense contracts 90 days after they're signed. FY2027 began October 1, 2026; it's left out until Defense data for it starts to arrive.
Who wins PSC R424 contracts
| Company | Obligated, last 3 years |
|---|---|
| Georgia Tech Applied Research Corp | $56.9 million |
| Bates White, LLC | $51 million |
| Analysis Group Inc | $48.3 million |
| The Brattle Group Inc | $36.1 million |
| Cornerstone Research Inc | $30 million |
| Berkeley Research Group, LLC | $29.6 million |
| FTI Consulting, Inc. | $26.2 million |
| Keystone Strategy LLC | $12.5 million |
| Cra International, Inc. | $12.5 million |
| Morgan, Angel, Brigham & Associates L.L.C. | $12.1 million |
Large prime contractors (companies that hold the contract with the agency) subcontract part of their work to small businesses. See which primes subcontract, by NAICS code.
Research PSC R424 work
By the NAICS codes this work goes with, the one with the most spending first: who won recently, contracts ending soon, agencies' planned buys and the large primes that subcontract it, nationwide. Each code shows only the pages that exist for it:
- 541199 All Other Legal Services: planned buys · large primes that subcontract. Not available for 541199 yet: who won recently or contracts ending in the next 12 months. Its NAICS page shows who buys it.
- 541990 All Other Professional, Scientific, and Technical Services: who won recently · contracts ending in the next 12 months · planned buys · large primes that subcontract
- 541690 Other Scientific and Technical Consulting Services: who won recently · planned buys · large primes that subcontract
Related PSC codes
- R401 Support – Professional: Personal Care (Non-Medical)
- R402 Support – Professional: Real Estate Brokerage
- R403 Real Estate Brokerage Services
- R404 Support – Professional: Land Surveys – Cadastral (Non-Construction)
- R405 Support – Professional: Operations Research/Quantitative Analysis
- R406 Support – Professional: Policy Review/Development
- R407 Program Evaluation Services
- R408 Support – Professional: Program Management/Support
- R409 Program Review/Development Services
- R410 Support – Professional: Program Evaluation/Review/Development
Frequently asked questions
What is PSC R424?
R424 is the service code in the federal Product and Service Code (PSC) Manual named “Support – Professional: Expert Witness”, under R (Support SVCS (Prof, Admin, MGMT)) and R4 (Professional Services). Agencies put a PSC on every contract to record what they bought.
What is the difference between a PSC and a NAICS code?
A PSC describes what the government is buying. A NAICS code describes the industry of the business doing the work, and it sets the SBA size standard for small business set-asides. Every contract notice has both.
Which NAICS code goes with PSC R424?
Most federal contract dollars under PSC R424 go with NAICS 541199 (All Other Legal Services), according to USAspending.gov. The contracting officer picks the NAICS code for each solicitation, so check the notice.
How do I find contracts that use PSC R424?
Contract opportunities are posted on SAM.gov with their PSC and NAICS codes. 1 open notice uses PSC R424 right now. FedReady can match new ones to your business and email you, free.
Keep going
Sources: SAM.gov Contract Opportunities, USAspending.gov and the PSC Manual. How we count.