OSHA ITA API Submission Guide for Multi-Establishment Employers

OSHA's ITA offers an API so recordkeeping systems can submit establishment and 300A data, and case data where required, without manual portal entry. It needs an API token from the ITA account, and it only helps if the data is validated before it is sent.

Large employers need repeatable electronic filing that does not depend on manual portal work.

Covered establishments submit injury data to OSHA's Injury Tracking Application (ITA) by March 2 each year for the previous calendar year; for 2026 data that is March 2, 2027 (29 CFR 1904.41). Three groups must submit: establishments with 250 or more employees that must keep records (300A data); establishments with 20 to 249 employees in an industry listed in Appendix A to Subpart E (300A data); and establishments with 100 or more employees in an industry listed in Appendix B (300A data plus 300 and 301 case data). Headcount means every individual employed at any time in the prior year, including part-time, seasonal, and temporary workers, and every submission includes the establishment's EIN.

Use the API only after establishment data and OSHA form outputs pass field-level validation. Most ITA problems are establishment data problems: an old NAICS code, a parent-company EIN, or a headcount measured at the wrong level. The fix is to decide coverage per establishment in the fall, clean the EIN, NAICS, and address data then, and leave only validation and submission for February.

Whatever you use should make these easy to keep and retrieve:

• The coverage decision for each establishment: peak headcount, NAICS code, and which appendix applies
• The EIN used by each establishment
• The submitted file or payload and the ITA confirmation
• Notes on any corrections made after submission

1. Validate the source data.
2. Generate payloads per establishment.
3. Submit and read each response.
4. Store confirmations and reconcile rejections.

If you are building the integration, treat validation and error handling as the product; the upload itself is the easy part.

Keep these in mind when you compare approaches:

• Teams automate upload before cleaning source data and then scale their errors.
• API submission still needs human review, confirmation, and correction handling.
• An establishment may use a number or code as its name in the ITA, as long as the submission includes a legal company name.

Whatever you choose, name one source of truth for each establishment and make every form, rate, and ITA file come from it. Most recordkeeping failures come from two records of the same case that disagree.

A 90-site employer connects its recordkeeping system to the ITA API. A February run submits 87 establishments; 3 are rejected for missing EINs after an acquisition. Finance supplies the EINs, the three are resubmitted the next day, and every response is stored with the 2026 records.

300log validates EIN and NAICS formats, produces ITA-ready CSV files for the 300A and for case data, and can authorize auto-filing of 300A data once you connect an ITA API token.

For a quick answer without an account, use the free ITA coverage checker.

• OSHA ITA CSV Validation Errors: How to Fix Rejected Rows Before the Deadline
• Form 301 Electronic Submission Privacy: Fields OSHA Excludes From Publication
• EIN for OSHA ITA: Multi-Establishment Filing Questions
• March 2 OSHA ITA Filing Checklist: CSV Upload and Final Confirmation