BOI stands for Beneficial Ownership Information (BOI) Reporting.
Effective January 1, 2024, many companies in the United States must report information about their beneficial owners—the individuals who ultimately own or control the company—to the Financial Crimes Enforcement Network (FinCEN), a bureau of the U.S. Department of the Treasury.
Filing is simple, secure, and free of charge. Beneficial ownership information reporting is not an annual requirement. Unless a company needs to update or correct information, a report only needs to be submitted once.
Companies required to report are called reporting companies. Reporting companies may have to obtain information from their beneficial owners and report that information to FinCEN.
Your company may need to report information about its beneficial owners if it is:
Twenty-three types of entities are exempt from beneficial ownership information reporting requirements, including publicly traded companies, nonprofits, and certain large operating companies.

Full details for exemptions at: https://www.fincen.gov/sites/default/files/shared/BOI_Small_Compliance_Guide.v1.1-FINAL.pdf.
You can file online at https://boiefiling.fincen.gov/.
New businesses have 90 days to complete the report after initial filing, but any businesses that registered prior to January 1, 2024, have until the end of the year
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