| Alabama | Required | Alabama Private Investigation Board (APIB) | Limited — 1 state |
| Alaska | Not required | Alaska Dept. of Commerce — business license (no state PI board; cities may license) | Not applicable |
| Arizona | Required | Arizona Dept. of Public Safety — Licensing | None |
| Arkansas | Required | Arkansas State Police — Private Investigators & Security | Limited — 3 states |
| California | Required | California Bureau of Security & Investigative Services (BSIS) | Limited — 5 states |
| Colorado | Not required | Colorado DORA (PI licensing status uncertain — confirm) | Not applicable |
| Connecticut | Required | Connecticut DESPP — Special Licensing & Firearms | Seek legal advice |
| Delaware | Required | Delaware State Police — Board of Examiners (PIs & Private Security) | Seek legal advice |
| District of Columbia | Required | DC Metropolitan Police — Security Officers Management Branch | Seek legal advice |
| Florida | Required | Florida FDACS — Division of Licensing | Limited — by agreement |
| Georgia | Required | Georgia Board of Private Detective & Security Agencies (SOS) | Limited (30-day) |
| Hawaii | Required | Hawaii DCCA — Board of Private Detectives & Guards | Seek legal advice |
| Idaho | Not required | No statewide PI licensing board | Not applicable |
| Illinois | Required | Illinois Dept. of Financial & Professional Regulation (IDFPR) | Seek legal advice |
| Indiana | Required | Indiana PLA — Private Investigator & Security Guard Licensing Board | Seek legal advice |
| Iowa | Required | Iowa Department of Public Safety | Limited — by permit |
| Kansas | Required | Kansas Attorney General — Private Detective Licensing | Seek legal advice |
| Kentucky | Required | Kentucky Board of Licensure for Private Investigators | Limited — 1 state |
| Louisiana | Required | Louisiana State Board of Private Investigator Examiners (LSBPIE) | Limited — by agreement |
| Maine | Required | Maine State Police — Licensing Division | Limited — by agreement |
| Maryland | Required | Maryland State Police — Licensing Division | Seek legal advice |
| Massachusetts | Required | Massachusetts DCJIS — Dept. of Criminal Justice Information Services | Seek legal advice |
| Michigan | Required | Michigan LARA — Professional Investigator Licensing | Seek legal advice |
| Minnesota | Required | Minnesota Board of Private Detective & Protective Agent Services | Seek legal advice |
| Mississippi | Not required | No statewide PI licensing board | Not applicable |
| Missouri | Required | Missouri Board of Private Investigator & Private Fire Investigator Examiners | Seek legal advice |
| Montana | Required | Montana Board of Private Security | Seek legal advice |
| Nebraska | Required | Nebraska Secretary of State — Private Detectives | Seek legal advice |
| Nevada | Required | Nevada Private Investigators Licensing Board (PILB) | Seek legal advice |
| New Hampshire | Required | New Hampshire State Police — Permits & Licensing | Seek legal advice |
| New Jersey | Required | New Jersey State Police — Private Detective Unit | Seek legal advice |
| New Mexico | Required | New Mexico RLD — Private Investigations Advisory Board | Seek legal advice |
| New York | Required | New York Dept. of State — Division of Licensing Services | Seek legal advice |
| North Carolina | Required | North Carolina Private Protective Services Board (NCDPS) | Limited — by agreement |
| North Dakota | Required | North Dakota Private Investigation & Security Board | Seek legal advice |
| Ohio | Required | Ohio Dept. of Public Safety — PISGS | Seek legal advice |
| Oklahoma | Required | Oklahoma CLEET — Private Investigator Licensing | Limited — by agreement |
| Oregon | Required | Oregon DPSST — Dept. of Public Safety Standards & Training | Limited — by agreement |
| Pennsylvania | Required | Pennsylvania — County Court of Common Pleas (Private Detective Act of 1953) | Seek legal advice |
| Rhode Island | Required | Rhode Island State Police (confirm licensing unit) | Seek legal advice |
| South Carolina | Required | South Carolina SLED — State Law Enforcement Division | Limited — 1 state |
| South Dakota | Not required | No statewide PI licensing board | Not applicable |
| Tennessee | Required | Tennessee PI & Polygraph Commission (Commerce & Insurance) | Limited — by agreement |
| Texas | Required | Texas DPS — Private Security Program | Seek legal advice |
| Utah | Required | Utah Division of Professional Licensing (DOPL) | Seek legal advice |
| Vermont | Required | Vermont OPR — Board of Private Investigative & Security Services | Seek legal advice |
| Virginia | Required | Virginia Dept. of Criminal Justice Services (DCJS) | Limited — by agreement |
| Washington | Required | Washington Dept. of Licensing — Private Investigative Agencies | Limited — 90-day permit |
| West Virginia | Required | West Virginia Secretary of State — PI & Security Guard Licensure | Seek legal advice |
| Wisconsin | Required | Wisconsin Dept. of Safety & Professional Services (DSPS) | Seek legal advice |
| Wyoming | Not required | No statewide PI licensing board | Not applicable |