Compliance calendar for US employers
Reviewed by Mellow Editorial Team, HR & payroll content team
A US employer compliance calendar is a structured schedule of recurring federal and state filing deadlines — payroll tax deposits, quarterly returns, annual reporting, and notices — that keeps your business on the right side of the IRS, SSA, and state agencies throughout the year.
Missing a single deadline can trigger penalties that compound quickly. The guide below organizes the major obligations by frequency so you can build them into your internal processes.
Ongoing: payroll tax deposits
Deposits are not quarterly events — they happen on a schedule tied to your tax liability.
The IRS assigns employers either a monthly or semiweekly deposit schedule based on a lookback period. Monthly depositors send funds by the 15th of the following month. Semiweekly depositors follow a tighter cadence: payroll run on Wednesday, Thursday, or Friday requires a deposit by the following Wednesday; payroll run on Saturday through Tuesday requires a deposit by the following Friday.
What you are depositing covers:
- Federal income tax withheld from employee wages
- Employee Social Security (6.2% up to the annual wage base) and Medicare (1.45%, no cap)
- The employer's matching share of both Social Security and Medicare
If your total tax liability exceeds $100,000 on any single day, a next-business-day deposit rule kicks in regardless of your assigned schedule.
All federal payroll tax deposits must go through the Electronic Federal Tax Payment System (EFTPS). Paper checks are not an acceptable substitute.
Quarterly: Form 941
Every quarter, employers file Form 941, the Employer's Quarterly Federal Tax Return. It reconciles what you withheld and deposited against what was actually owed.
| Quarter | Period covered | Due date |
|---------|---------------|----------|
| Q1 | January – March | April 30 |
| Q2 | April – June | July 31 |
| Q3 | July – September | October 31 |
| Q4 | October – December | January 31 |
If you made all required deposits on time and in full, the IRS gives you ten additional calendar days to file. Very small employers (annual liability of $1,000 or less) may qualify to file Form 944 annually instead of quarterly — but only if the IRS has specifically notified them to do so.
State payroll returns follow their own schedules. Most states mirror the federal quarterly pattern, but some require monthly filings. Check your state agency's requirements directly.
Annual: W-2s, 1099s, and year-end returns
January is the heaviest month on the compliance calendar.
January 31 is the deadline to:
- Furnish Form W-2 to each employee showing their wages, withheld taxes, and other compensation
- File copies of W-2s with the Social Security Administration (SSA)
- Send Form 1099-NEC to each independent contractor paid $600 or more during the tax year, and file copies with the IRS
Getting W-2s and 1099-NECs out on the same day they are due to the agencies removes any ambiguity. Build in a week of processing time to catch errors before the deadline.
Form 940 — the annual Federal Unemployment Tax (FUTA) return — is due January 31 as well. FUTA deposits themselves are due quarterly if your cumulative liability exceeds $500, so this is a year-round obligation that culminates in the annual return.
If you offer employer-sponsored health coverage and filed 250 or more W-2s in the prior year, you are required to report the cost of that coverage in Box 12 of each W-2. Applicable Large Employers (ALEs) under the Affordable Care Act also face annual reporting requirements through Forms 1094-C and 1095-C, with employee copies due by early March and IRS filing typically due by the end of March (electronic filers).
New hires and ongoing notices
Compliance is not only about tax filings. Several obligations attach at the point of hire or on a rolling basis:
- New hire reporting: Federal law requires employers to report each new hire to their state's new hire directory within 20 days of the start date. States may set shorter windows.
- Form I-9: Complete Section 1 on or before the employee's first day. Complete Section 2 within three business days of the start date. Retain I-9s for the longer of three years from the hire date or one year after employment ends.
- W-4: Collect before the first paycheck. No submission to the IRS is required unless the IRS requests it, but you must keep it on file.
- FLSA postings: Federal law requires specific workplace posters to be displayed where employees can see them. Several states add their own required postings.
State-specific notice requirements vary widely. California, for example, mandates a written notice of pay rate, pay day, and employer information at the time of hire — and prohibits most non-compete agreements. How Mellow runs payroll across six countries covers how these jurisdiction-by-jurisdiction differences play out in a multi-state or global context.
Building a working calendar
Map every deadline above onto a shared internal calendar, assign a named owner to each item, and set a reminder at least two weeks in advance. Treat the deposit schedule as a standing recurring task rather than a one-off event.
State and local deadlines shift the picture further. If you operate across multiple states, each one has its own unemployment insurance account, withholding return schedule, and new hire portal. Centralizing that information in one place — even a simple spreadsheet — is the practical minimum for staying current.
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