Business Code 238900: Coverage, Reporting, and SBA Size Standard

Business code 238900 is the industry-group label the federal statistical system uses for “Other Specialty Trade Contractors,” but the code you actually put on a tax return or federal registration is the six-digit version, 238990, titled “All Other Specialty Trade Contractors.”¹ The four-digit group 2389 gets padded with zeros to 238900 when the Bureau of Labor Statistics and similar agencies publish aggregated wage and employment data, but the reportable code on Schedule C, Form 1120, and SAM.gov is 238990.²

What This Code Covers

238990 is a residual category for specialty construction trades that don’t have their own dedicated NAICS classification. It covers new construction, additions, alterations, maintenance, and repairs performed by contractors whose primary work falls outside foundation work, building equipment installation, finishing trades, or site preparation.¹

The Census Bureau’s illustrative examples include:

Fence installation, residential and commercial
Outdoor swimming pool construction
Driveway and private parking lot paving or sealing
Interlocking brick and paver installation for patios and walkways
Scaffold erecting and dismantling at construction sites
Steeplejack work on steeples, smokestacks, and similar tall structures
Manufactured home setup and tie-down
Billboard erection
Crane rental with an operator
Sandblasting building exteriors

The common thread is a niche construction activity that clearly sits in the construction sector but is too specific for its own six-digit code. If your primary revenue comes from one of these activities and no more specific NAICS code fits, 238990 is likely the right pick.

What Does Not Belong Under 238990

Contractors often land on 238990 by default when a more specific code actually applies. The Census Bureau flags several activities that look like they belong here but don’t:¹

Excavation, grading, demolition, dirt moving, septic installation, and land clearing go under 238910 (Site Preparation Contractors), not 238990.³
Paving public streets and highways falls under 237310. The paving that stays here is private driveways and parking lots.
Renting construction equipment without an operator is a leasing business (532412), not a construction trade.
Cleaning and maintaining an existing swimming pool is a building service (561790), not pool construction.
Asbestos removal, lead paint abatement, and similar hazardous material work goes under 562910.
Installing invisible pet containment fencing is classified as electrical work (238210).
Indoor swimming pool construction falls under commercial building construction (236220).

The trickiest line for outdoor contractors is between construction and landscaping. A company that primarily installs fences, patios, or retaining walls as standalone construction projects belongs in the construction sector. A company that provides landscape design and maintenance and installs those structures as part of a broader landscaping package typically belongs under 561730 (Landscaping Services). The deciding factor is where the majority of revenue comes from.

Where You Report the Code

The code appears in a few different places depending on how your business is set up.

Tax Returns

Sole proprietors enter the principal business activity code on Schedule C (Form 1040), line B.⁴ C-corporations enter it on Form 1120, Schedule K, lines 2a through 2c, alongside a description of the business activity and principal product or service.⁵ S-corporations report it on Form 1120-S in the same manner. The IRS uses these codes for statistical benchmarking, comparing your revenue and expense ratios against businesses reporting the same code.

SAM.gov and Federal Contracting

Any business pursuing federal contracts must register with SAM.gov and identify its NAICS codes there.⁶ You can list multiple codes covering different lines of work, but your primary code should reflect where most of your revenue comes from. Contracting officers assign a NAICS code to each solicitation, and your registered codes determine which set-aside opportunities you can bid on.

SBA Small Business Size Standard

For 238990, the SBA defines a small business as one with average annual receipts of $19.0 million or less.⁷ That number is not last year’s revenue. The SBA calculates it as total receipts over the most recently completed five fiscal years, divided by five.⁸ Businesses in operation for less than five complete fiscal years use receipts over their actual period of operation, divided by the number of weeks and multiplied by 52.

Receipts means all revenue from any source, reduced by returns and allowances, roughly corresponding to total income plus cost of goods sold as reported on your tax return. Staying under the $19.0 million threshold matters most for federal contracting set-asides. If your five-year average crosses the line, you lose small business status for solicitations coded to 238990.

How to Choose the Right Code

The rule is straightforward: your primary NAICS code should reflect the activity that produces the largest share of your annual revenue. If you install fences and also do some driveway sealing, and fence work brings in 70% of your income, your primary code is based on fence installation.

Start with the Census Bureau’s NAICS lookup and search for the most specific six-digit code that matches your primary activity.⁹ Only fall back to 238990 after confirming that no more specific code fits. If your primary work is electrical, plumbing, concrete, roofing, or any of the dozens of trades with dedicated codes, those codes take priority even if you occasionally do 238990-type work on the side.

If your business evolves and your primary revenue source shifts, update the code. On SAM.gov, edit your NAICS codes through the entity registration portal under Core Data. On your tax return, you simply enter the new code the following year. There is no separate IRS process for changing a previously reported code, because you report it fresh each filing year.

What Happens If You Pick the Wrong Code

A wrong NAICS code on a tax return doesn’t by itself trigger an IRS penalty. The code is used for statistical analysis, not to calculate what you owe. But if your income and expense ratios look unusual for the industry your code places you in, it can flag your return for closer review.

The serious consequences are on the federal contracting side. Different NAICS codes carry different size standards, so using a code with a higher revenue threshold than 238990’s $19.0 million could make a non-small business appear to qualify for small business set-asides. Willfully misrepresenting size status to win a set-aside contract triggers a presumption of loss to the government equal to the total contract amount, and can lead to suspension or debarment from federal contracting, civil liability under the False Claims Act, and criminal prosecution under the Small Business Act with potential fines and imprisonment.¹⁰ Those penalties target willful misrepresentation rather than honest mistakes, but the safer course is to get the code right from the start.

1
Census Bureau. North American Industry Classification System (NAICS) – 238990
2
U.S. Bureau of Labor Statistics. NAICS 238900 – Other Specialty Trade Contractors
3
Census Bureau. North American Industry Classification System (NAICS) – Subsector 238
4
Internal Revenue Service. Instructions for Schedule C (Form 1040) (2025)
5
Internal Revenue Service. Instructions for Form 1120 (2025)
6
U.S. Small Business Administration. Basic Requirements
7
eCFR. 13 CFR Part 121 – Small Business Size Regulations
8
eCFR. 13 CFR 121.104 – How Does SBA Calculate Annual Receipts
9
U.S. Census Bureau. North American Industry Classification System (NAICS)
10
eCFR. 13 CFR 121.108 – What Are the Penalties for Misrepresentation of Size Status