523991 — Trust, Fiduciary, and Custody Activities
Description
This U.S. industry comprises establishments primarily engaged in providing trust, fiduciary, and custody services to others, as instructed, on a fee or contract basis, such as bank trust offices and escrow agencies (except real estate) (as defined in the official U.S. Census Bureau 2022 NAICS Manual).
Overview Facts
Legacy SIC Concordance
Trace the historical mapping chain from the 1987 Standard Industrial Classification (SIC) to the modern 2022 NAICS code format.
- SIC 6091 - Nondeposit Trust Facilities (via SIC1987:6091→NAICS1997:523991→2002:523991→2007:523991→2012:523991→2017:523991→2022:523991)
- SIC 6099 - Functions Related to Depository Banking, NEC (via SIC1987:6099→NAICS1997:523991→2002:523991→2007:523991→2012:523991→2017:523991→2022:523991)
- SIC 6289 - Services Allied With the Exchange of Securities or Commodities, NEC (via SIC1987:6289→NAICS1997:523991→2002:523991→2007:523991→2012:523991→2017:523991→2022:523991)
- SIC 6733 - Trusts, Except Educational, Religious, and Charitable (via SIC1987:6733→NAICS1997:523991→2002:523991→2007:523991→2012:523991→2017:523991→2022:523991)
Suggested Product Service Codes (Advisory)
The following Product Service Codes (PSCs) are advisory suggestions aligned with this NAICS code. Note: NAICS and PSC codes map to different dimensions of procurement (industry vs. product/service). There is no official binding 1:1 crosswalk.
- PSC R711 — Banking Services(includes accepting and cashing government checks and other payment instruments, accepting direct deposits, accepting payments to the government from the public)
Source: DoD DPCAP PSC Selection Tool (Ingested: 2026-06-29)
Frequently Asked Questions (FAQ)
Is NAICS code 523991 valid in 2022? ▾
Yes, 523991 is a valid 6-digit 2022 NAICS national industry code representing 'Trust, Fiduciary, and Custody Activities' under Sector 52 in the official classification index.
What is the SBA size standard for NAICS code 523991? ▾
The Small Business Administration (SBA) has established a small business size standard of $47,000,000 for NAICS code 523991 (Trust, Fiduciary, and Custody Activities), calculated based on receipts.
What is the legacy SIC equivalent for NAICS 523991? ▾
According to official Census Bureau concordance tables, NAICS code 523991 (Trust, Fiduciary, and Custody Activities) maps to legacy 1987 Standard Industrial Classification (SIC) codes: 6091 - Nondeposit Trust Facilities, 6099 - Functions Related to Depository Banking, NEC, 6289 - Services Allied With the Exchange of Securities or Commodities, NEC, 6733 - Trusts, Except Educational, Religious, and Charitable.
Related Pages & Tools
Further regulatory reference links for NAICS code 523991:
- Sector 52 Directory Hub — List of related industries in the Finance and Insurance sector.
- SIC ↔ NAICS Crosswalk Tool — Look up mappings between legacy SIC codes and modern classifications.
- NAICS 523991 to SIC Crosswalk — Bidirectional mapping to legacy SIC codes (Trust, Fiduciary, and Custody Activities).
- SBA Size Standards Guide — Complete rules and averaging periods for small business classifications.
- Calculating Annual Receipts Guide — Detailed worked example of revenue calculation rules.
- IRS Principal Business Activity Guide — How NAICS codes map to corporate and entity tax filings.