What is the SBA size standard for NAICS 541990?

The SBA size standard for NAICS 541990 (All Other Professional, Scientific, and Technical Services) is $19.5 million in average annual receipts, per 13 C.F.R. § 121.201.

Which federal agencies buy under NAICS 541990?

For FY2024 reporting, the leading federal customers under NAICS 541990 were Department of Defense, Department of Homeland Security, Department of Justice, Department of State, Department of Health and Human Services. Live obligation data is available on USAspending.gov.

What FAR or DFARS clauses commonly apply to NAICS 541990 contracts?

Frequent clause flowdowns include FAR 52.219-14 (Limitations on Subcontracting); FAR 52.222-41 (Service Contract Labor Standards); FAR 52.227-14 (Rights in Data — General); FAR 52.222-50 (Combating Trafficking in Persons). Each contract instrument will incorporate clauses by reference under FAR 52.252-2; this list reflects the high-frequency set for this NAICS, not an exhaustive flowdown.

Professional, Scientific, Technical Services

NAICS 541990 — All Other Professional, Scientific, and Technical Services

Catch-all for technical services that do not map to a specific 541xxx code. Federal use spans translation, expert witness, weather forecasting, mapping, and miscellaneous technical advisory.

Quick facts

SBA size standard: $19.5 million; Average annual receipts · 13 C.F.R. § 121.201
FY2024 federal obligations: $1B–$2B; See live USAspending.gov data →

Top federal customers

Federal agencies that obligate the most spending under NAICS 541990 (FY2024 reporting period). Order tracks federal-obligation volume on USAspending.gov.

1.Department of Defense
2.Department of Homeland Security
3.Department of Justice
4.Department of State
5.Department of Health and Human Services

Set-aside fit

Whether NAICS 541990 commonly carries set-aside designations on federal awards. Eligibility for any specific solicitation is set by the contracting officer; this table reflects the FY2024 award pattern, not a guarantee of set-aside status.

SDVOSB (Service-Disabled Veteran-Owned Small Business)
8(a) Business Development Program
HUBZone Small Business
WOSB / EDWOSB
VOSB (Veteran-Owned Small Business)

Used when contracting officers cannot find a tighter NAICS fit. Set-aside eligibility is common but COs sometimes challenge the NAICS assignment.

Frequent prime contractors

Companies that most frequently appear as prime awardees under NAICS 541990 for FY2024. Drawn from USAspending.gov public award records — verify currency at the live link below.

Leidos
CACI International
SOS International
Calibre Systems
Booz Allen Hamilton
ICF International
MAXIMUS
SAIC
AECOM
Tetra Tech

See live award data on USAspending.gov →

Common FAR / DFARS clauses

Frequently flowed-down clauses on contracts in this NAICS. The clause text on acquisition.gov is authoritative; this list captures the practical pattern, not an exhaustive flowdown.

FAR 52.219-14Limitations on Subcontracting
Services-based limitation on set-aside awards.
FAR 52.222-41Service Contract Labor Standards
Service Contract Act applies when nonexempt service workers perform on a federal site.
FAR 52.227-14Rights in Data — General
Default data-rights position for technical reports and deliverables.
FAR 52.222-50Combating Trafficking in Persons
Standard services flowdown.

Indirect rate considerations

Service-firm three-pool structure. SCA-covered work requires fringe documentation aligned to the applicable wage determination. G&A on materials applies if any pass-through occurs.

See FieldLedger's Indirect Rate Engine for pool definition and rate tracking, or read the FieldLedger methodology for the underlying FAR Part 31 framework.

How FieldLedger fits NAICS 541990

Signed timekeeping and Indirect Rate Engine. SCA fringe tracking is the differentiator on Service Contract Act-covered tasks.

DCAA compliance →Indirect Rate Engine →DCAA readiness check →

Frequently asked

What is the SBA size standard for NAICS 541990?: The SBA size standard for NAICS 541990 (All Other Professional, Scientific, and Technical Services) is $19.5 million in average annual receipts, per 13 C.F.R. § 121.201.
Is NAICS 541990 eligible for SDVOSB, 8(a), HUBZone, or WOSB set-asides?: Set-aside programs that commonly apply: SDVOSB, 8(a), HUBZone, WOSB, VOSB. Used when contracting officers cannot find a tighter NAICS fit. Set-aside eligibility is common but COs sometimes challenge the NAICS assignment.
Which federal agencies buy under NAICS 541990?: For FY2024 reporting, the leading federal customers under NAICS 541990 were Department of Defense, Department of Homeland Security, Department of Justice, Department of State, Department of Health and Human Services. Live obligation data is available on USAspending.gov.
What FAR or DFARS clauses commonly apply to NAICS 541990 contracts?: Frequent clause flowdowns include FAR 52.219-14 (Limitations on Subcontracting); FAR 52.222-41 (Service Contract Labor Standards); FAR 52.227-14 (Rights in Data — General); FAR 52.222-50 (Combating Trafficking in Persons). Each contract instrument will incorporate clauses by reference under FAR 52.252-2; this list reflects the high-frequency set for this NAICS, not an exhaustive flowdown.
What indirect-rate structure works for a federal contractor in NAICS 541990?: Service-firm three-pool structure. SCA-covered work requires fringe documentation aligned to the applicable wage determination. G&A on materials applies if any pass-through occurs.
How does FieldLedger help small federal contractors in NAICS 541990?: Signed timekeeping and Indirect Rate Engine. SCA fringe tracking is the differentiator on Service Contract Act-covered tasks.

Sources

U.S. Census NAICS manual — census.gov/naics
SBA size-standards table — 13 C.F.R. § 121.201 (eCFR)
Federal obligations + prime awardees — USAspending.gov NAICS 541990
FAR / DFARS clause text — acquisition.gov

Snapshot date: 2026-05-08 (FY2024 reporting period). Federal-obligation bands and prime-contractor lists reflect the data as of the snapshot — refresh against USAspending.gov for current figures.