IRS Enforcement of ACA Employer Requirements

The Internal Revenue Service serves as the primary federal enforcement authority for Applicable Large Employer obligations under the Affordable Care Act, administering penalties under Internal Revenue Code Section 4980H and collecting information returns that document employer compliance. Enforcement operates through a structured notice-and-response process that can result in substantial assessments against employers who fail to offer qualifying coverage or who file inaccurate information returns. Understanding how IRS enforcement works — from the data triggers that initiate review to the formal penalty notice cycle — is essential for employers subject to the employer mandate.

Definition and scope

IRS enforcement of ACA employer requirements encompasses two distinct but related functions: assessing Employer Shared Responsibility Payments (ESRPs) under IRC § 4980H and enforcing the information reporting obligations established under IRC §§ 6055 and 6056. The regulatory context for ACA obligations traces authority for both functions to the ACA statutory text and subsequent Treasury regulations, primarily those finalized in 2014 (T.D. 9655, 26 CFR Part 54).

The scope of enforcement applies exclusively to Applicable Large Employers (ALEs) — organizations averaging 50 or more full-time equivalent employees in the prior calendar year. The IRS does not have independent authority to audit health plan design for consumer protection purposes; that function falls to the Department of Labor and HHS. IRS jurisdiction is limited to:

  1. Whether an ALE offered minimum essential coverage to at least 95 percent of full-time employees (the § 4980H(a) standard)
  2. Whether the coverage offered met affordability and minimum value thresholds under § 4980H(b)
  3. Whether Forms 1094-C and 1095-C were filed completely, accurately, and on time
  4. Whether penalty assessments are correctly calculated based on IRS data matching

The penalty authority does not self-execute — the IRS cannot assess a § 4980H penalty without first receiving a triggering event, which is a Marketplace subsidy determination for at least one full-time employee.

How it works

The enforcement mechanism operates through a four-stage sequence:

  1. Marketplace trigger — An employee purchases coverage through a federal or state ACA Marketplace and receives an advance premium tax credit. The Marketplace transmits this determination to the IRS, identifying the employer by EIN.

  2. Data matching — The IRS cross-references the Marketplace subsidy data against the employer's filed Forms 1094-C and 1095-C. This matching process identifies whether the employer reported offering coverage to the affected employee and whether the reported offer meets affordability and minimum value standards. Errors or missing codes on 1095-C forms can make compliant offers appear non-compliant in this match.

  3. Letter 226-J issuance — If the data match indicates a potential ESRP liability, the IRS issues Letter 226-J, the formal preliminary penalty assessment notice. The letter specifies the tax year under review, the calculated penalty amount, and the employee-level detail underlying the calculation. Employers typically receive 30 days to respond.

  4. Resolution and final notice — After reviewing the employer's response (submitted on Form 14764), the IRS issues either a closing letter (Letter 227 series) reducing or eliminating the proposed penalty, or proceeds to a Notice and Demand for Payment if the liability is sustained. Employers who disagree with a sustained assessment may pursue standard IRS appeals procedures.

The IRS processes ESRP assessments on a calendar-year basis, meaning enforcement for a given plan year typically begins 18 to 36 months after the close of that year. Penalty amounts under § 4980H(a) are calculated using a per-employee annualized rate, adjusted for inflation; the base rate established in statute is $2,000 per full-time employee above a 30-employee threshold (IRC § 4980H). The § 4980H(b) rate is $3,000 per employee who received a Marketplace subsidy, capped at the § 4980H(a) amount.

Common scenarios

Three enforcement scenarios account for the majority of Letter 226-J notices:

Scenario A — ALE fails to offer coverage to 95 percent of full-time employees. An employer with 200 full-time employees offers coverage to only 180 (90 percent). This falls below the 95 percent threshold, triggering § 4980H(a) liability if even one employee receives a Marketplace subsidy. The penalty is calculated on 170 employees (200 minus the 30-employee offset), not only on those who received subsidies.

Scenario B — Coverage offered is unaffordable or fails minimum value. An employer offers coverage meeting the 95 percent threshold, but the employee premium contribution exceeds the applicable affordability percentage for the year. Employees who receive Marketplace subsidies create § 4980H(b) exposure for the employer at the $3,000 annualized rate per subsidized employee.

Scenario C — Reporting errors that create phantom liability. An employer correctly offered qualifying coverage but used incorrect or incomplete line codes on Form 1095-C, causing the IRS data match to conclude no offer was made. This is one of the most common sources of Letter 226-J notices and is fully correctable through the response process. Errors on Form 1095-C are among the most frequent causes of erroneous assessments that employers must dispute with supporting documentation.

The IRS also assesses information reporting penalties under IRC § 6721 and § 6722 for late, missing, or inaccurate returns, with per-return penalties that increase for larger organizations. These penalties apply independently of any ESRP assessment.

Decision boundaries

The IRS enforcement framework draws several operationally significant distinctions that determine penalty exposure:

§ 4980H(a) vs. § 4980H(b): The (a) penalty applies when no qualifying offer was made to the employee population at the 95 percent threshold; the (b) penalty applies when an offer was made but that offer failed affordability or minimum value. The (a) penalty uses a workforce-wide calculation; the (b) penalty is individually triggered. An employer cannot face both penalties for the same employee in the same month.

ALE vs. non-ALE: Employers below the 50 full-time equivalent threshold face no § 4980H liability and no § 6056 reporting obligation, though § 6055 reporting requirements may still apply to self-insured plans regardless of size.

Full-time vs. non-full-time employee: The IRS calculates penalties based on full-time employees only (30+ hours per week), not on full-time equivalents. FTEs enter the ALE determination calculation but do not drive penalty exposure directly.

Correct offer vs. incorrect reporting: Employers who made a qualifying offer but reported it incorrectly occupy a different procedural position than employers who never made an offer. The former category can resolve liability through documentation; the latter requires substantive compliance remediation. The ACA overview resource distinguishes these scenarios in the context of broader compliance obligations.

The affordability safe harbors — W-2 wages, rate of pay, and federal poverty line — function as defenses within the enforcement process. An employer that correctly applied a safe harbor and documented that application in its plan design and reporting retains the ability to assert the safe harbor as a complete defense to § 4980H(b) liability during the Letter 226-J response window.

References

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