How WARN Act 60-day notice periods are calculated and what counts as valid notice

The federal WARN Act generally requires covered employers to provide at least 60 calendar days' advance notice before a mass layoff or plant closing takes effect. The notice period is measured from the date notice is given to the date job losses are scheduled, so workers should compare those two dates on any filing. Notice is typically delivered in person, through a union, or by mail, and keeping the letter, envelope, and accompanying materials can be important if timeliness is disputed. Federal rules require notice to go to affected workers or their union, the state dislocated worker unit, and the local chief elected official, and a valid notice must specify the site, the type of action, the expected date, and whether job losses are permanent or temporary. Informal announcements do not start the clock, and short notice can result in back pay and benefits for the shortfall period, though the law includes narrow exceptions.