The WARN Act Explained: The 60-Day Layoff Notice Law

The WARN Act is the reason large US layoffs rarely come as a complete surprise. Short for the Worker Adjustment and Retraining Notification Act, this 1988 federal law requires certain employers to give workers advance notice before major layoffs and plant closures.

What the WARN Act requires

Covered employers must provide 60 calendar days' written notice before a plant closing or mass layoff — to affected workers (or unions), the state dislocated worker unit, and the local chief elected official.

Which employers are covered

Employers with 100 or more full-time employees. Private businesses, nonprofits, and quasi-public entities can all be covered.

What counts as a triggering event

• Plant closing: shutdown of a single site with job losses for 50+ full-time employees in any 30-day period.
• Mass layoff: at a single site in any 30-day period — 500+ full-time employees, or 50–499 if they make up at least 33% of the active full-time workforce there.

An aggregation rule combines job losses across 90 days to prevent splitting one layoff to dodge notice.

What the notice must contain

Site name and address, expected date, permanent or temporary, job titles and headcount, and a contact person — which is why WARN filings are such a rich public data source.

Exceptions (interpreted narrowly)

1. Faltering company (plant closings only)
2. Unforeseeable business circumstances
3. Natural disaster

Employers must still give as much notice as practicable.

Penalties

Back pay and benefits per worker for each day of violation (up to 60 days), plus civil penalties up to $500/day. WARN class actions are well-established.

State mini-WARN laws go further

• California: 75+ employees, 60 days
• New York: 50+ employees, 90 days
• Illinois: 75+ employees, 60 days
• New Jersey: 90 days + mandatory severance

Differing thresholds mean WARN data is richer in some states — state comparisons need this context.

What WARN data can and cannot tell you

The best public window into large-scale US layoffs — but reported plans, not confirmed job losses.

Data source: Layoff Atlas tracks US WARN notices by company, state, and effective date.