OSHA 300 Log: Requirements, Posting Deadline, and How It Differs From the 300A
The OSHA 300 Log is the year-round injury and illness log most covered employers must keep; the 300A is the annual summary of that log, required to be posted in a visible location from February 1 through April 30 regardless of how many recordable cases occurred (29 CFR 1904.32); the 301 is the incident-level detail behind each entry. Separately, employers meeting electronic-submission thresholds — 250+ employees at an establishment in a covered industry, or 100+ employees at an establishment in a designated high-hazard industry — must submit data through OSHA's Injury Tracking Application (ITA) each year.
The three OSHA forms, and how they differ
"OSHA 300 log" gets used loosely to mean three related but distinct documents under 29 CFR Part 1904:
| Form | What it is | Posted? |
|---|---|---|
| Form 300 | The running log — one line per recordable case, updated all year | No |
| Form 300A | Year-end summary of the 300 log's totals, with a certifying signature | Yes — Feb 1 to Apr 30 |
| Form 301 | Incident-level detail behind a single recordable case | No |
When someone searches "OSHA 300 log requirements," they're usually really asking about the 300A's posting rule, since that's the one with a hard calendar deadline. This guide covers all three, since getting the 300A right depends on having the 300 log accurate first.
When the 300A must be posted
Under 29 CFR 1904.32, the 300A summarizing calendar year Y must be posted from February 1 through April 30 of year Y+1, in a location where employees normally see notices — a break room bulletin board, not a filing cabinet. This applies even in a year with zero recordable cases: a "no cases" 300A still has to go up.
Do you have to submit anything electronically?
Posting the 300A satisfies the display requirement, but some employers separately owe an electronic submission through OSHA's Injury Tracking Application (ITA). Broadly, as of this writing:
- Establishments with 250 or more employees in an industry covered by the recordkeeping rule submit their 300A data.
- Establishments with 100 or more employees in a designated high-hazard industry (a specific list under Appendix B — includes construction and several manufacturing sectors) submit 300, 300A, and 301 data.
Both the employee-count thresholds and the high-hazard industry list have been revised before and could be again — confirm the current rule on OSHA's ITA page rather than assuming last year's thresholds still apply.
The 7-calendar-day rule most logs miss
Under 29 CFR 1904.29, a recordable case has to be entered on the 300 log within seven calendar days of the employer learning it happened — not seven business days, and not "by the time someone gets around to updating the spreadsheet." This is where a shared file usually breaks down: the incident happens on-site, but the person who maintains the log is often somewhere else entirely, and the two don't sync up inside the window.
You also don't have to keep the log on paper or OSHA's own form. Digital substitutes are explicitly permitted under 29 CFR Part 1904, as long as the record captures every field OSHA's Form 300 requires. The rule is about what data you keep, not what software you keep it in.
Why a spreadsheet usually isn't enough
A lot of small employers start their 300 log in Excel, and it works fine right up until it doesn't: the 300A totals have to be calculated by hand from the log every year, a shared spreadsheet has no record of who changed what or when, and there's nothing stopping a cell from getting edited after the fact — which matters if a claim or an inspection ever turns on the original numbers. None of that makes a spreadsheet non-compliant on its own, but it does mean the accuracy of your 300A rests entirely on someone remembering to do the math correctly, every year, with no audit trail if a number gets questioned later — and, per the 7-day rule above, on that same person hearing about the incident in time.
IncidentLog keeps the 300 log automatically as incidents get filed, computes the 300A totals for you, and locks each entry into a tamper-evident record the moment it's filed — the log updates the moment a report is submitted from the job site, not whenever someone remembers to open the spreadsheet.
How to stay compliant, step by step
- Confirm you're a covered employer. Most employers with more than 10 employees are covered, unless your industry is on OSHA's partially-exempt list (29 CFR 1904 Subpart B, Appendix A) — see the security-guard and daycare guides for two examples.
- Log each recordable case on Form 300 as it happens. Every work-related injury or illness that meets OSHA's recordable criteria (death, days away, job transfer/restriction, medical treatment beyond first aid, loss of consciousness, or a significant diagnosed condition) gets a line on the 300 log, not just the ones you remember at year-end.
- Total the year's cases and hours onto Form 300A. At year-end, add up case counts, days-away counts, and total hours worked across the establishment, plus the certifying executive's name, title, and signature.
- Post the 300A from February 1 through April 30. It has to be displayed somewhere employees normally see notices, even if the total is zero recordable cases for the year.
- Check whether you owe an electronic submission. If your establishment meets the size/industry thresholds, submit the required data through OSHA's Injury Tracking Application (ITA) by the annual deadline — confirm the current thresholds and due date on OSHA's ITA site, since both have changed before.
Frequently asked questions
What is the OSHA 300 log?
It's the year-round log of every work-related injury and illness that meets OSHA's recordability criteria — one line per case, updated throughout the year as incidents happen. It stays on file at the establishment; it isn't the document that gets posted.
When is the OSHA 300A due?
The 300A summary must be posted in a visible location at the establishment from February 1 through April 30 of the year following the one it summarizes (29 CFR 1904.32) — regardless of whether any recordable incidents occurred that year. It isn't "due" to OSHA on a specific date; it's a posting requirement, not a submission deadline, unless your establishment also owes an electronic ITA submission.
What's the difference between the OSHA 300 log and the 300A?
The 300 log is the running, case-by-case record kept all year. The 300A is the year-end summary of that log's totals — case counts, days away, injury/illness types — plus establishment info and an executive's certifying signature. The 300A is what gets posted; the 300 log doesn't.
What are the OSHA 300 log posting requirements?
Only the 300A summary gets posted, not the 300 log itself (which can contain details some employers prefer to keep less visible). It must be posted where employees can reasonably see it, for the full February 1 – April 30 window, even in a zero-incident year.
Do I need to submit the OSHA 300 log electronically?
Only if your establishment meets OSHA's size and industry thresholds for the Injury Tracking Application (ITA): broadly, establishments with 250 or more employees in a covered industry submit their 300A data, and establishments with 100 or more employees in a designated high-hazard industry submit 300, 300A, and 301 data. These thresholds have been updated before, so confirm the current rule on OSHA's ITA site rather than assuming last year's figures still apply.
When is the OSHA 300A due this year?
The posting window is fixed by regulation, not the calendar year: whatever year you're in, the prior year's 300A goes up February 1 and comes down April 30 (29 CFR 1904.32). There's no separate "due date" announced each year — if you're asking because a deadline is approaching, check today's date against that February 1–April 30 window rather than searching for a year-specific number.
What is the purpose of the OSHA 300 log?
It gives OSHA, employees, and employers a standardized, year-round record of work-related injuries and illnesses at each establishment — the point is to make injury patterns visible (which tasks, shifts, or locations keep producing recordable cases) rather than just to satisfy a filing requirement. The 300A posting exists so employees can see that record too, not just OSHA.
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