One Site or Many? How the WARN Act Defines a Single Site of Employment

When a company announces layoffs at several locations, one question decides whether the federal WARN Act even applies: do those locations count as one site of employment, or several? The Act's thresholds — 100 or more full-time workers, or 50 to 99 workers making up at least a third of the site's workforce — are measured site by site, not company-wide. So the definition of a "single site of employment" can be the difference between a required 60-day notice and no notice at all.

What the regulation says

The federal regulation, 20 CFR 639.3(i), starts with the simple case: a single site of employment is a single location. But it goes further. A group of contiguous locations that form a campus or industrial park counts as one site, and so do separate facilities across the street from each other. A factory and its warehouse next door are one site, not two.

If separate employers operate in one office building, each employer's operation is its own site.

Workers who do not have a fixed workplace get a different rule. For employees whose duties require travel from point to point, who are outstationed, or whose work is done outside the employer's regular sites — railroad workers, bus drivers, travelling sales staff are the regulation's examples — the single site is the location they are assigned to as a home base, the place their work is assigned from, or the place they report to.

Why the definition changes the outcome

Consider a company that lays off 40 workers at each of three separate, non-contiguous facilities. Company-wide, that is 120 workers — comfortably above the 100-worker threshold. But if each facility is its own single site of employment, no single site reaches the threshold, and the federal WARN Act may not require notice for any of the three layoffs.

Now consider the reverse: a campus closure. A company shuts down a site made up of several buildings in one industrial park, laying off 150 workers across those buildings. Because the buildings form one contiguous site, the layoffs are counted together, and the threshold is met easily. Workers reading a WARN filing for that closure will see one notice covering all the buildings, not one notice per building.

This is also why the 90-day aggregation rule, which adds together smaller layoffs at the same site over 90 days, is applied site by site. Layoffs at different sites do not get combined to reach the threshold.

What this means for reading the registry

Layoff Atlas currently lists 704 WARN notices affecting 66,156 reported workers in its 90-day window, with 33 counts unavailable. Those figures are counts of notices and reported workers, not confirmed job losses: they describe reported plans, not confirmed job losses, and coverage varies by state.

When you look at an individual filing, the location in the notice is doing real legal work. A filing for 135 workers at a single SeaTac facility, effective December 31, 2026, is a single-site story. A filing for 169 workers at a corporate headquarters in Bala Cynwyd, Pennsylvania, is also a single-site story. Neither can be added to a filing at a different facility to reach a threshold, and neither should be read as a company-wide total.

The same caution applies to state totals. Washington leads the current window with 17,073 reported workers, followed by California with 14,224, Illinois with 4,626, Texas with 3,652, and Ohio with 3,180. Those are sums of many separate single-site filings, not one employer's decision. A state can rank high because it has many sites with filings, because a few large sites filed, or both.

The calendar ahead

The weeks ahead show how single-site filings add up across the country without ever being a single event. The registry shows 5,206 workers with effective dates in the week of October 25, followed by 4,565 in the week of November 1, 5,311 in the week of November 8, 7,781 in the week of November 15, 6,527 in the week of November 22, and 5,832 in the week of November 29. Each of those weekly totals is made of separate filings at separate sites, each measured against the threshold on its own.

Questions worth asking about any filing

If you are checking whether a layoff near you should have come with a WARN notice, the site question comes before the headcount question. Ask: where is the single site of employment, and how many workers at that site are affected? A company-wide announcement number can mislead in either direction — overstating a single site's layoffs, or hiding that no single site crossed the line.

State mini-WARN laws can change the answer. Some states use lower thresholds or cover smaller employers, so a layoff that falls short of the federal site threshold may still require notice under state law. The federal definition is the starting point, not the whole picture.

The single-site rule is easy to overlook because most coverage of layoffs talks about companies, not sites. But the WARN Act was written site by site, and its protections trigger site by site. Reading the filings that way — one site at a time — is the only way the numbers make sense.

Data source: Layoff Atlas