> Enrich.chat gives AI agents verified work emails and mobiles. To use it from an agent, read https://enrich.chat/agents.md . This is the Markdown version of https://enrich.chat/naics/561611/ # NAICS code 561611: Investigation and Personal Background Check Services The companies classified under NAICS 561611, where they are based, how big they are and how the code maps to SIC. By Enrich.chat Editorial. Updated October 22, 2026. **Short answer:** NAICS 561611 is the code for Investigation and Personal Background Check Services, in sector 56: Administrative and Support and Waste Management and Remediation Services. The companies counted under it are mostly very small: 70% have 50 or fewer employees, and 87% are headquartered in the United States. ## What is NAICS 561611? NAICS 561611 is the code for Investigation and Personal Background Check Services. It belongs to sector 56: Administrative and Support and Waste Management and Remediation Services. NAICS, the North American Industry Classification System, is the standard U.S. government agencies use to sort businesses by what they mainly do, and each digit narrows the category. Most of the companies counted also carry SIC 7381, Detective and armored car services, in the older SIC system (91%). NAICS is a North American system, so companies outside the US, Canada and Mexico are placed in it by classification. - 70% of the companies counted have 50 or fewer employees, and the middle one is in the 11 to 50 range. - The largest group is headquartered in the United States (87%). Within the US, New York is the biggest state (11%). - Most were founded in the 2000s (34%), then the 1990s (31%). **Figure: How NAICS 561611 is built.** The code 561611 split into its parts: sector 56, then subsector, industry group, NAICS industry and U.S. industry. *The six digits of NAICS 561611. Each digit narrows the category.* ## Which companies are classified under NAICS 561611? The biggest by headcount range include Agb Investigative Services, Mintz Group, Abc Legal Services, Digistream Investigations and Phersei Srl. Names link to a company profile where we have one. | Company | Headquarters | Employees | | --- | --- | --- | | Agb Investigative Services | Chicago, IL | 501 to 1,000 | | Abc Legal Services | Seattle, WA | 201 to 500 | | Digistream Investigations | Davis, CA | 201 to 500 | | Phersei Srl | Milano, Italy | 201 to 500 | | Prosegur SA - Società Di Vigilanza | Lugano, Switzerland | 201 to 500 | | Ss8 Networks | Milpitas, CA | 51 to 200 | | Nefco Fire Investigations | Rochester, NH | 51 to 200 | | Command Investigations | Lake Mary, FL | 51 to 200 | | Abbrevia | Trento, Italy | 51 to 200 | | Corporate Investigations India | New Delhi, India | 51 to 200 | | Photofax | Hampshire, IL | 51 to 200 | | Private Eyes | Greenville, NC | 51 to 200 | | Information Discovery Services | Fort Worth, TX | 51 to 200 | | Truview Bsi | Melville, NY | 51 to 200 | | Merge Investigations | Lancaster, PA | 51 to 200 | | Accurate Biometrics | Itasca, IL | 51 to 200 | | Abacus Research | Greensboro, NC | 51 to 200 | | Phenix Investigations | Greenwood, IN | 51 to 200 | | Shadow Investigations | Livonia, MI | 51 to 200 | | Beacon International Group | Columbus, OH | 51 to 200 | | Lauth Investigations International | Indianapolis, IN | 11 to 50 | | Harris Investigations | Lansdale, PA | 11 to 50 | | Impact Intelligence And Investigations | Dallas, TX | 11 to 50 | | Troy Group | Chicago, IL | 11 to 50 | | Advancing Real Change | Baltimore, MD | 11 to 50 | The table shows the 25 biggest by headcount range, with ties broken by audience size. The charts and percentages below cover every company counted for this page, not just these 25, and companies with fewer than 11 employees are not counted. Headquarters is the location on each company's public profile. ## Where are NAICS 561611 companies based? The largest groups are headquartered in the United States (87%), the United Kingdom (4%) and Italy (4%). **Figure: Where companies in NAICS 561611 are based.** Bars for the share of counted companies in NAICS 561611 headquartered in each country: United States 87%, United Kingdom 4%, Italy 4%. *Share of counted companies in NAICS 561611 by headquarters country.* Within the United States, New York (11%), California (10%) and Texas (10%) lead. **Figure: US headquarters of companies in NAICS 561611, by state.** A tile map of the United States shaded by the share of counted US companies in NAICS 561611 headquartered in each state. The largest are New York 11%, California 10%, Texas 10%. *Share of counted US companies in NAICS 561611 by headquarters state. The three largest states are outlined.* ## How big are the companies counted for NAICS 561611? 70% of them have 50 or fewer employees, and the middle one is in the 11 to 50 range. Companies with fewer than 11 employees are not counted. **Figure: Size of companies in NAICS 561611.** Seven columns for the share of counted companies in NAICS 561611 in each employee range: 11 to 50 70%, 51 to 200 23%, 201 to 500 6%, 501 to 1,000 1%, 1,001 to 5,000 0%, 5,001 to 10,000 0%, 10,001+ 0%. *Share of counted companies in NAICS 561611 in each employee range.* ## How NAICS 561611 compares - 70% of companies in NAICS 561611 have 50 or fewer employees, against 60% across all NAICS codes on this site. - Michigan holds 8% of the US companies here, against 3% across all NAICS codes on this site. ## How do NAICS 561611 companies describe themselves? A code is assigned by classification, and a company does not choose its own, so the label a company uses for itself can differ. The most common labels here are Security and Investigations (68%), Legal Services (16%) and Information Services (6%). **Figure: How companies in NAICS 561611 describe themselves.** Bars for the share of counted companies in NAICS 561611 that give each industry on their public profile: Security and Investigations 68%, Legal Services 16%, Information Services 6%, Insurance 6%. *Share of counted companies in NAICS 561611 by the industry they list on their public profile.* ## NAICS 561611 and the SIC system NAICS replaced SIC in 1997, but the two do not line up one to one: companies filed under one NAICS code can carry several SIC codes. These are the ones seen most. | Code | Title | Share of counted | | --- | --- | --- | | SIC 7381 | Detective and armored car services | 91% | | SIC 7389 | Business services | 2% | ## Where NAICS codes come from NAICS is maintained by the U.S. Census Bureau with Canada and Mexico and revised every five years; the current edition is NAICS 2022. To check exactly what a code includes, search the [official NAICS index](https://www.census.gov/naics/) or read the Census Bureau's [guide to understanding NAICS](https://www.census.gov/programs-surveys/economic-census/year/2022/guidance/understanding-naics.html). Pick a code by what a company mostly does, not by who it sells to. ## How do you reach the people at NAICS 561611 companies? The people to talk to are usually operations, HR and finance leaders. You can build the list from this code in three prompts to your AI agent. ### 1. Count them (free) Counting who matches never uses credits. ```text Use www.enrich.chat to count the companies with NAICS code 561611 (Investigation and Personal Background Check Services) ``` ### 2. Find the people (5 credits per person) Name the roles you sell to. Each person returned is 5 credits, and name, title and company are included. ```text Use www.enrich.chat to find the operations, HR and finance leaders at companies with NAICS code 561611, with their titles ``` ### 3. Get their work emails (10 credits each) An email is 10 credits only when one is found. Every email comes with a status: verified, catch-all or unknown. ```text Use www.enrich.chat to find the work emails for these people and tell me which ones are verified ``` ## More to explore Codes next to it: [NAICS 561612: Security Guards and Patrol Services](https://enrich.chat/naics/561612/)[NAICS 561621: Security Systems Services](https://enrich.chat/naics/561621/)[NAICS 561622: Locksmiths](https://enrich.chat/naics/561622/) Others in sector 56: [NAICS 561311: Employment Placement Agencies](https://enrich.chat/naics/561311/)[NAICS 561510: Travel Agencies](https://enrich.chat/naics/561510/)[NAICS 561730: Landscaping Services](https://enrich.chat/naics/561730/)[NAICS 561720: Janitorial Services](https://enrich.chat/naics/561720/)[NAICS 561312: Executive Search Services](https://enrich.chat/naics/561312/)[NAICS 561320: Temporary Help Services](https://enrich.chat/naics/561320/)[NAICS 561710: Exterminating and Pest Control Services](https://enrich.chat/naics/561710/)[NAICS 561520: Tour Operators](https://enrich.chat/naics/561520/) ## Frequently asked questions ### What is NAICS code 561611? NAICS 561611 is the code for Investigation and Personal Background Check Services, in sector 56: Administrative and Support and Waste Management and Remediation Services. ### What is the SIC code for NAICS 561611 (Investigation and Personal Background Check Services)? 91% of the companies counted carry SIC 7381 (Detective and armored car services), but the two systems do not map one to one. ### Which companies are classified under NAICS 561611? The biggest by headcount range include Agb Investigative Services, Mintz Group, Abc Legal Services, Digistream Investigations and Phersei Srl. The page lists 25 with links to their profiles where we have them. ### Where are NAICS 561611 companies based? The largest groups are headquartered in the United States (87%), the United Kingdom (4%) and Italy (4%). ### How big are the companies in NAICS 561611? 70% have 50 or fewer employees, and the middle one is in the 11 to 50 range. Companies with fewer than 11 employees are not counted. ### How do I find a company's NAICS code? Search the official NAICS index at the U.S. Census Bureau for the code that matches what the company mostly does. Public companies in the US also list a SIC code in their SEC EDGAR profile. ## Try this prompt Find the people at NAICS 561611 companies ```text Use www.enrich.chat to find the operations, HR and finance leaders at companies with NAICS code 561611, with titles and verified work emails ``` ## Related - [Companies using a technology](https://enrich.chat/companies-using/) - [NAICS 561612](https://enrich.chat/naics/561612/) - [NAICS 561621](https://enrich.chat/naics/561621/) - [NAICS 561622](https://enrich.chat/naics/561622/) - [Tech stack lookup](https://enrich.chat/tools/tech-stack-lookup/)