---
kind: "section"
citation: "29 U.S.C. § 2101"
title: "29"
title_heading: "Labor"
number: "2101"
heading: "Definitions; exclusions from definition of loss of employment"
release: "119-102"
date: "2026-07-12"
url: "https://uscodex.org/usc/29/2101"
units:
  - "Chapter 23 — Worker Adjustment and Retraining Notification"
---

# §2101. Definitions; exclusions from definition of loss of employment

- (a) **Definitions—** As used in this chapter—
  - (1) the term “employer” means any business enterprise that employs—
    - (A) 100 or more employees, excluding [part-time employees](#a-8); or
    - (B) 100 or more employees who in the aggregate work at least 4,000 hours per week (exclusive of hours of overtime);
  - (2) the term “plant closing” means the permanent or temporary shutdown of a single site of employment, or one or more facilities or operating units within a single site of employment, if the shutdown results in an [employment loss](#a-6) at the single site of employment during any 30-day period for 50 or more employees excluding any [part-time employees](#a-8);
  - (3) the term “mass layoff” means a reduction in force which—
    - (A) is not the result of a [plant closing](#a-2); and
    - (B) results in an [employment loss](#a-6) at the single site of employment during any 30-day period for—
      - (i)
        - (I) at least 33 percent of the employees (excluding any [part-time employees](#a-8)); and
        - (II) at least 50 employees (excluding any [part-time employees](#a-8)); or
      - (ii) at least 500 employees (excluding any [part-time employees](#a-8));
  - (4) the term “representative” means an exclusive representative of employees within the meaning of section [159(a)](/usc/29/159.md?p=a) or [158(f)](/usc/29/158.md?p=f) of this title or [section 152 of title 45](/usc/45/152.md);
  - (5) the term “affected employees” means employees who may reasonably be expected to experience an [employment loss](#a-6) as a consequence of a proposed [plant closing](#a-2) or [mass layoff](#a-3) by their [employer](#a-1);
  - (6) subject to [subsection (b)](#b), the term “employment loss” means (A) an employment termination, other than a discharge for cause, voluntary departure, or retirement, (B) a layoff exceeding 6 months, or (C) a reduction in hours of work of more than 50 percent during each month of any 6-month period;
  - (7) the term “unit of local government” means any general purpose political subdivision of a State which has the power to levy taxes and spend funds, as well as general corporate and police powers; and
  - (8) the term “part-time employee” means an employee who is employed for an average of fewer than 20 hours per week or who has been employed for fewer than 6 of the 12 months preceding the date on which notice is required.
- (b) **Exclusions from definition of employment loss—**
  - (1) In the case of a sale of part or all of an [employer](#a-1)’s business, the seller shall be responsible for providing notice for any [plant closing](#a-2) or [mass layoff](#a-3) in accordance with [section 2102 of this title](/usc/29/2102.md), up to and including the effective date of the sale. After the effective date of the sale of part or all of an [employer](#a-1)’s business, the purchaser shall be responsible for providing notice for any [plant closing](#a-2) or [mass layoff](#a-3) in accordance with [section 2102 of this title](/usc/29/2102.md). Notwithstanding any other provision of this chapter, any person who is an employee of the seller (other than a [part-time employee](#a-8)) as of the effective date of the sale shall be considered an employee of the purchaser immediately after the effective date of the sale.
  - (2) Notwithstanding [subsection (a)(6)](#a-6), an employee may not be considered to have experienced an [employment loss](#a-6) if the closing or layoff is the result of the relocation or consolidation of part or all of the [employer](#a-1)’s business and, prior to the closing or layoff—
    - (A) the [employer](#a-1) offers to transfer the employee to a different site of employment within a reasonable commuting distance with no more than a 6-month break in employment; or
    - (B) the [employer](#a-1) offers to transfer the employee to any other site of employment regardless of distance with no more than a 6-month break in employment, and the employee accepts within 30 days of the offer or of the closing or layoff, whichever is later.

## Source credit

(Pub. L. 100–379, § 2, Aug. 4, 1988, 102 Stat. 890.)

## Notes

### Statutory Notes and Related Subsidiaries

### Effective Date

Pub. L. 100–379, § 11, Aug. 4, 1988, 102 Stat. 895, provided that: “This Act [enacting this chapter] shall take effect on the date which is 6 months after the date of enactment of this Act [Aug. 4, 1988], except that the authority of the Secretary of Labor under section 8 [section 2107 of this title] is effective upon enactment.”

### Short Title

Pub. L. 100–379, § 1(a), Aug. 4, 1988, 102 Stat. 890, provided that: “This Act [enacting this chapter] may be cited as the ‘Worker Adjustment and Retraining Notification Act’.”