Choosing category systems
How to choose between NAICS, PSC, NIGP, UNSPSC, and Assistance Listings when interpreting GovTribe category fields.
Category systems classify different parts of government-market activity. Do not treat NAICS, PSC, NIGP, UNSPSC, and Assistance Listings as interchangeable.
Quick model
| Category system | Meaning | Use when asking |
|---|---|---|
| NAICS | Industry classification. | What industry is connected to this vendor or procurement? |
| PSC | Federal product or service classification. | What product or service did the federal buyer classify this as? |
| NIGP | State and local commodity or service classification. | What state and local procurement commodity or service category applies? |
| UNSPSC | Global product and service classification often used by state and local sources. | What product or service category did this source use or map to? |
| Assistance Listings / CFDA | Federal assistance program structure. | What grant or assistance program does this funding belong to? |
Which category should I use?
| Question | Use | Why |
|---|---|---|
| I want to size a federal contracting industry. | NAICS and PSC together. | NAICS gives industry context; PSC gives product/service context. |
| I want to find vendors by business line. | NAICS. | Vendor profiles and federal procurements often carry NAICS industry context. |
| I want to compare what federal buyers purchased. | PSC. | PSC is the federal product/service code family for contract activity. |
| I want state and local commodity/service demand. | NIGP or UNSPSC. | State and local sources commonly use commodity taxonomies rather than federal PSC. |
| I want grant program context. | Federal grant program and CFDA/Assistance Listing context. | Grants are organized around assistance programs, not NAICS or PSC. |
GovTribe field mapping
| GovTribe field or data type | Category role | Related article |
|---|---|---|
naics_category and naics_categories | Industry classification for federal contracting, vendors, and some user workflows. | NAICS category |
psc_category and psc_categories | Federal product/service classification for contract activity. | PSC category |
nigp_category and nigp_categories | State and local commodity/service classification. | NIGP category |
unspsc_category and unspsc_categories | Product/service classification used by many state and local sources. | UNSPSC category |
federal_grant_program and cfda_number | Federal assistance program or Assistance Listing context. | Federal grant program |
funding_activity_categories | Grants.gov funding activity categories on grant opportunities. | Funding activity categories |
Common mistakes
- Do not use NAICS as a product code. NAICS describes industry, not the specific item or service purchased.
- Do not use PSC as a vendor industry profile. PSC is tied to federal contract product/service classification.
- Do not expect NIGP or UNSPSC on federal contract records. They are mainly useful for state and local procurement data in GovTribe.
- Do not use Assistance Listings as procurement categories. They describe federal assistance programs such as grants, loans, scholarships, insurance, and other assistance awards.
- When a record has multiple category systems, use the one that matches the question and keep the others as context.
Official source notes
- Census NAICS describes NAICS as the standard used by federal statistical agencies to classify business establishments by industry.
- Acquisition.gov PSC Manual is the official Product and Service Code manual source.
- NIGP Code describes NIGP as a commodity and service taxonomy used in procurement systems.
- UNDP UNSPSC describes UNSPSC as an open global product and service classification standard.
- SAM.gov Assistance Listings describes Assistance Listings as public descriptions of federal programs that provide grants, loans, scholarships, insurance, and other assistance awards.
- Grants.gov synopsis guidance describes funding instrument type, funding activity category, post date, and close date fields on grant opportunities.
Related articles
- Federal contract data model: Understand where category fields appear across federal contract records.
- Federal grant data model: Understand how assistance programs connect to opportunities and awards.
- State and local contract data model: Understand how NIGP and UNSPSC appear in state and local records.
- Source identifiers and record matching: Use GovTribe IDs, classification codes, source identifiers, and related fields when comparing records.
Source identifiers and record matching
How to use GovTribe IDs, source identifiers, PIIDs, solicitation numbers, grant numbers, UEIs, source URLs, and originating-record links when matching GovTribe records.
Federal grant data model
How federal grant opportunities, transactions, awards, sub-awards, and assistance programs fit together in GovTribe.