HR Compliance Calendar: Every Federal Deadline and Filing Requirement

Compliance deadlines are not distributed evenly. January and February carry an enormous concentration — W-2s, 1099s, Form 940, the fourth-quarter 941, ACA statements, and the start of OSHA posting all land within a few weeks — while stretches of the year are almost empty.

That concentration is why the work has to start in October. This calendar lays out every federal deadline for 2027, with the weekend and holiday shifts already applied, so you can build the reverse schedule that actually makes January survivable.

Two caveats before you use this. The dates below apply the weekend-and-holiday shift rule against the expected 2027 federal holiday schedule — [VERIFY that schedule]. And no state deadlines are included, because every state sets its own for withholding, unemployment, and reporting. Build the state layer separately.

January

The last item is the one that quietly breaks. Indexed figures — Social Security wage base, retirement contribution limits, HSA limits, state minimum wages, state paid leave contribution rates — all reset on January 1. A payroll configuration that was correct in December is wrong in January unless someone updated it.

February

Note the W-2 date has no extension advantage. Electronic filing does not buy additional time, and the automatic 30-day extension no longer exists — an extension must be requested on Form 8809 for specific hardship reasons.

The February 15 W-4 sweep is a small task that is almost universally forgotten. Calendar it with an owner.

March

Electronic filing is mandatory once you file an aggregate of 10 or more information returns across all form types combined. [VERIFY the current threshold.] This catches small employers who previously filed a handful of W-2s and a few 1099s on paper.

The heaviest planning month of the year, even though few filings are due.

November and December

The fringe benefit posting deadline is the most consequential item on this list and it has no official date. Personal use of company vehicles, group-term life imputed income, gift cards, and third-party sick pay must be run through payroll before the final check of the year. Identify them in January and there are no wages left to withhold FICA from — meaning the employer effectively funds it.

Dates You Must Confirm Each Year

Three significant deadlines are not fixed and must be looked up:

1. EEO-1 Component 1. The EEOC announces the filing window each cycle and it has shifted substantially from year to year. Do not assume last year's schedule. [VERIFY the 2027 window.]
2. Affirmative action plan cycles for federal contractors, which run on the contractor's own plan year.
3. State deadlines — withholding deposits and returns, unemployment wage reports, annual reconciliations, paid leave contributions, and state pay data reports. None follow the federal pattern. See our HR Training by State resources.

Building the Calendar That Actually Works

1. Put every deadline in a shared calendar with a named owner, not a spreadsheet nobody opens.
2. Set reminders at 30 and 7 days, not on the due date.
3. Add the state layer as a separate track, per jurisdiction.
4. Build backward from January. The February 1 wall requires work completed in October, November, and December. Schedule the preparation, not just the deadline.
5. Assign a backup owner for every item. Filing deadlines do not accommodate vacations or departures.
6. Review the calendar in October for the coming year, updating for new jurisdictions, new thresholds crossed, and changed requirements.
7. Keep proof of filing for everything, with the submission confirmation.

Frequently Asked Questions

When are W-2s due in 2027?

February 1, 2027, for both employee copies and the SSA filing, because January 31 falls on a Sunday. Electronic filing does not provide additional time.

When is Form 5500 due in 2027?

August 2, 2027, for calendar-year plans, because July 31 falls on a Saturday. Filing Form 5558 extends the deadline to October 15, 2027.

How long must the OSHA 300A summary be posted?

From February 1 through April 30. Covered establishments must also submit the data electronically by March 2.

When is the Medicare Part D creditable coverage notice due?

Before October 15 each year, to all Medicare-eligible individuals covered by the plan — including covered spouses and dependents, not only employees over 65.

What happens if a deadline falls on a weekend?

It moves to the next business day. Several 2027 dates shift for this reason, including the January 31, July 31, and October 31 deadlines.

When is the EEO-1 due?

The EEOC announces the filing window each cycle, and it has moved substantially between years. Confirm the current window rather than assuming the prior year's dates.

The Bottom Line

Work backward from February 1. Everything that makes January manageable — fringe benefit posting, employee data verification, third-party sick pay, imputed income, next-year payroll configuration — happens in October, November, and December. Put the calendar somewhere shared, name an owner and a backup for each item, and remember that this covers only the federal layer.

For structured support, work through our HR Compliance Checklists and Year-End Checklist, or explore our HR Compliance Training.