ACA Compliance for Staffing Agencies and PEOs

Staffing agencies and Professional Employer Organizations (PEOs) occupy a structurally unique position under the Affordable Care Act because the workers they supply or co-employ are distributed across multiple client organizations — complicating both the determination of Applicable Large Employer (ALE) status and the assignment of coverage obligations. Understanding how the IRS and the Department of Labor allocate employer responsibilities in these arrangements is essential for avoiding penalties under Internal Revenue Code Section 4980H. This page covers the definitions that govern these relationships, the mechanics of compliance, common operational scenarios, and the boundaries that separate one employer's obligations from another's.

Definition and scope

Under the ACA's employer mandate framework, the term "employer" defaults to the common-law standard: the entity that directs and controls the work performed by a worker. The IRS codified this standard in final regulations issued under 26 C.F.R. § 54.4980H, which governs assessable payments for failure to offer minimum essential coverage.

Staffing agencies are businesses that recruit workers and place them with client companies under a temporary or contract arrangement. The agency typically issues the W-2, withholds payroll taxes, and may or may not offer health coverage. The client company directs the work.

Professional Employer Organizations (PEOs) operate under a co-employment model. The PEO enters into a client service agreement and becomes the employer of record for HR and benefits purposes, while the client retains operational control. The National Association of Professional Employer Organizations (NAPEO) defines a PEO as providing "integrated HR services" through this co-employment relationship.

For ACA purposes, the scope question involves two layers:

  1. ALE determination — whether the staffing agency, the client, or both cross the 50 full-time equivalent (FTE) employee threshold that triggers mandate obligations (IRS Publication 5196).
  2. Coverage obligation — which entity is required to offer minimum essential coverage that meets affordability and minimum value standards, and which entity bears exposure to Section 4980H(a) or 4980H(b) penalties.

The regulatory context for ACA rules governing employer classification draws heavily on the common-law employer standard rather than the contractual arrangement the parties prefer.

How it works

The compliance mechanism for staffing agencies and PEOs follows a structured sequence:

  1. Identify the common-law employer. The IRS looks at who has the right to control the worker — not who pays the worker. A client company that directs how, when, and where a placed worker performs duties is likely the common-law employer for ACA mandate purposes, regardless of which entity issues the paycheck.

  2. Count employees toward ALE status. Each entity counts its own common-law employees (full-time and FTE) when determining whether it meets the 50-FTE threshold. If a staffing agency retains common-law employer status over its placed workers, those workers count toward the agency's ALE calculation. If the client is the common-law employer, those same workers count toward the client's total.

  3. Assign the coverage obligation. Under IRS guidance, the common-law employer bears the obligation to offer qualifying coverage. A staffing agency that is the common-law employer of placed workers must offer coverage to those who average 30 or more hours per week during a measurement period — or risk 4980H penalties.

  4. Apply controlled group and aggregation rules. Related entities under common ownership are aggregated for ALE determination under Internal Revenue Code Sections 414(b), 414(c), 414(m), and 414(o). A PEO and its affiliates are not automatically aggregated with client companies simply because of the service agreement, but ownership tests still apply.

  5. Document the arrangement. PEOs and staffing firms should maintain written agreements that specify which entity offers health coverage, to whom, and on what terms. The IRS uses Form 1095-C reporting to cross-reference coverage offers with individual marketplace premium tax credit claims.

The ACA compliance overview at the site index provides orientation to the broader set of requirements that apply alongside the employer mandate.

Common scenarios

Scenario 1: Staffing agency as common-law employer
A staffing firm places 85 workers at a manufacturing client site. The staffing firm sets hourly rates, disciplines workers, and controls the terms of engagement. Because the staffing firm is the common-law employer, it must count all 85 workers in its ALE calculation and offer compliant coverage to those averaging ≥30 hours per week. The client has no Section 4980H exposure for these workers unless it also qualifies as their common-law employer.

Scenario 2: Client as common-law employer
A technology company engages a staffing agency for 40 long-term contractors. The company assigns projects, reviews performance, and has the right to discharge. The IRS would likely classify the technology company as the common-law employer. Those 40 workers count toward the company's ALE threshold, not the agency's. If the company fails to offer compliant coverage, it faces potential 4980H(b) penalties — currently indexed but with a base structure described in IRS Revenue Procedure 2024-40 for the relevant plan year.

Scenario 3: PEO co-employment
A PEO provides HR services under a client service agreement to a 60-person restaurant group. The PEO is the employer of record and offers health coverage through its own group plan. The restaurant group retains operational control. For ACA reporting, the PEO typically files Form 1094-C and Form 1095-C on behalf of the client using the client's EIN, as described in IRS Notice 2013-54 and later ACA reporting guidance. The restaurant group remains the ALE and retains the underlying compliance obligation — the PEO's offer of coverage satisfies the mandate only if the offer meets affordability and minimum value standards applicable to the client's workforce.

Scenario 4: Dual coverage offer
In some staffing arrangements, both the agency and the client offer health coverage. The IRS position under Treas. Reg. § 54.4980H-1(a)(6) is that an employee has only one common-law employer at a time. When a dual offer exists, the offer from the common-law employer is the one that determines whether a qualifying offer was made for 4980H purposes. The non-employer party's offer does not substitute for the obligation.

Decision boundaries

Distinguishing which entity bears ACA employer obligations requires applying specific tests rather than relying on contract labels.

Common-law employer vs. contractual employer
The IRS applies a 20-factor common-law test (originally articulated in Revenue Ruling 87-41) to determine who controls the worker. Contract language stating "the agency is the employer of record" does not override IRS classification. The controlling factors include: who sets work hours, who provides tools, who has the right to discharge, and whether the worker performs services as a core part of the business.

PEO arrangements: ALE remains with the client
Even when a PEO is the employer of record for payroll purposes, the client organization is generally treated as the ALE responsible for the employer mandate. The PEO satisfies the mechanics of the offer and handles Form 1095-C filing, but the client's employee count — not the PEO's aggregate workforce across all clients — determines ALE status for that client. Each client of a PEO is assessed independently under the 50-FTE threshold.

Staffing agency ALE calculation
A staffing agency that retains common-law employer status over workers at multiple client sites must aggregate all such workers when calculating its own FTE count. If the agency's total common-law workforce across all placements reaches 50 FTEs, the agency is an ALE and must comply with the mandate for those workers. Conversely, a client company that has common-law employer status over staffed workers must count them in the client's own ALE determination.

Variable hour and measurement period application
Staffing agencies frequently deal with part-time and variable-hour employees whose average hours fluctuate week to week. The IRS permits use of look-back measurement periods — typically 3 to 12 months — to determine whether such workers cross the 30-hours-per-week threshold and therefore must be offered coverage during the subsequent stability period. Staffing firms must apply consistent measurement period rules across similarly situated worker categories, as defined under 26 C.F.R. § 54.4980H-3.

Reporting responsibility
For ACA information reporting under IRC Sections 6055 and 6056, the filing obligation follows the ALE determination. An ALE that uses a PEO may authorize the PEO to file Forms 1094-C and 1095-C on its behalf, but the ALE remains responsible for the accuracy and timeliness of those filings. IRS penalties for late or incorrect reporting are assessed against the ALE's EIN, not the PEO's, unless a specific written authorization shifts that responsibility — and even then, the IRS treats the client as the responsible party for assessment purposes.

References

The law belongs to the people. Georgia v. Public.Resource.Org, 590 U.S. (2020)