IRC 4980H: ACA Employer Shared Responsibility Payment Practitioner Guide

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Scope and Currency Notice

This guide covers the IRC 4980H employer shared responsibility framework for CPAs, enrolled agents, and tax practitioners advising employers on ACA compliance, responding to IRS Letter 226-J, and determining ALE status for tax years 2024 through 2026. The 2026 affordability percentage is stated in Rev. Proc. 2025-29; verify the current year percentage at IRS.gov before advising clients on plan design or affordability safe harbor compliance. Penalty amounts under IRC 4980H(a) and 4980H(b) are indexed annually; verify current figures at IRS.gov. The One Big Beautiful Bill Act (OBBBA) did not amend IRC 4980H; the employer shared responsibility structure is unchanged, but practitioners should confirm whether OBBBA or subsequent legislation has affected the premium tax credit rules under IRC 36B, which are the trigger for both 4980H penalties. All statutory citations and regulatory references must be verified at IRS.gov before being relied on in any specific client matter.

Key Practitioner Points: IRC 4980H Employer Mandate

  • ALE threshold (50 FTEs): An employer is an Applicable Large Employer for a calendar year if it averaged at least 50 full-time employees (including FTEs) on business days during the preceding calendar year. ALE status is determined at the controlled group level under IRC 414.
  • 4980H(a) vs. 4980H(b): The threshold decision in every ESRP defense is which subsection applies. 4980H(a) fires when the ALE fails to offer minimum essential coverage to at least 95% of full-time employees; 4980H(b) fires when coverage is offered but is not affordable or does not provide minimum value. The two penalties are mutually exclusive per employee per month.
  • PTC trigger: Neither 4980H(a) nor 4980H(b) generates a penalty unless at least one full-time employee of the ALE actually receives a premium tax credit (PTC) under IRC 36B for that year. ESRP enforcement is driven by Form 1095-C and Marketplace data cross-referencing.
  • Affordability safe harbors: Three IRS-approved methods allow an ALE to demonstrate coverage is affordable without individual employee income data: W-2 wages, rate of pay, and the federal poverty line. The 2026 affordability percentage is per Rev. Proc. 2025-29; verify at IRS.gov.
  • Letter 226-J: IRS enforcement of TY2022 and TY2023 has accelerated significantly. Receipt of Letter 226-J triggers a 90-day response window. An untimely or no response converts the proposed ESRP into an assessed liability triggering collection.
  • Forms 1094-C and 1095-C: These are the ALE's annual filing obligation. Errors in B-series codes and Part II Line 14/15/16 coding are the most common source of erroneous Letter 226-J proposals. Correcting the underlying 1095-C reporting is often the most efficient abatement pathway.
  • Controlled group trap: A single employer that appears to be below 50 FTEs may still be an ALE when related entities are aggregated under IRC 414. Practitioners advising multi-entity clients must perform the aggregation analysis first.

The IRC 4980H employer shared responsibility payment is the ACA's primary enforcement mechanism for employer-sponsored health coverage. For tax years 2022 and 2023, the IRS significantly increased Letter 226-J issuance, meaning practitioners advising employers now regularly receive penalty proposals running from tens of thousands of dollars to seven figures or more. The 4980H(a) versus 4980H(b) framework is the threshold question in every engagement: which subsection fired, why, and whether the penalty calculation and the underlying employee data are correct. This guide walks through the complete framework, from ALE determination through Letter 226-J response, with the controlled group traps and affordability safe harbor mechanics that are the core of every ACA compliance defense.

All statutory citations, regulatory references, penalty amounts, and affordability percentages in this guide must be verified against the current text of the Internal Revenue Code, applicable Treasury Regulations, and current IRS guidance at IRS.gov before being relied on in any specific client matter. This guide is for informational purposes only and does not constitute legal or tax advice.

Section 1: ALE Determination -- The 50 Full-Time Equivalent Threshold

The IRC 4980H employer mandate applies only to Applicable Large Employers. ALE status is not self-reported in real time; it is determined prospectively based on the workforce count in the preceding calendar year. The first step in every ACA compliance engagement is to confirm whether the client is an ALE for the year at issue.

Full-Time Employees: The 30-Hour Rule

A full-time employee is an employee who is employed on average at least 30 hours of service per week, or at least 130 hours of service per calendar month. The 130-hour monthly equivalent is the standard used for monthly measurement periods. An employer uses either a monthly measurement method or a look-back measurement method to track full-time status; each has distinct rules and safe harbor protections. Verify the current IRS guidance on measurement methods at IRS.gov and in the final regulations under IRC 4980H before advising clients on method selection.

Full-Time Equivalents (FTEs): Counting Part-Time Hours

Full-time equivalent employees are calculated by aggregating all hours of service of non-full-time employees for a month and dividing that total by 120. For example, if 40 part-time employees each work 60 hours per month, the FTE count is (40 x 60) / 120 = 20 FTEs. FTEs are added to the count of full-time employees to determine whether the 50-employee threshold is met for ALE purposes. However, FTEs are not separately counted for penalty calculation purposes: only actual full-time employees (those averaging 30 or more hours per week) are counted in the 4980H penalty computation.

The Seasonal Employee Exception

An employer whose workforce exceeded 50 full-time employees (including FTEs) for no more than 120 days during the calendar year is not an ALE, provided the employees who caused the employer to exceed the 50-employee threshold were seasonal workers. Seasonal workers are those who perform labor or services on a seasonal basis as defined by the Secretary of Labor, including workers whose employment is ordinarily not expected to exceed 6 months in duration. Employers relying on the seasonal exception should document the dates, headcount, and job classifications supporting that position.

Practitioner Note: ALE Status Is Determined One Year in Advance

ALE status for a given calendar year is determined by the workforce in the preceding calendar year. A business that first exceeds 50 full-time employees (including FTEs) in 2025 will be an ALE subject to IRC 4980H for 2026. Practitioners advising rapidly growing businesses must track headcount through the prior year to give timely ACA compliance advice. A newly established employer that was not in existence in the preceding calendar year is treated as an ALE only if it reasonably expects to employ an average of at least 50 full-time employees on business days during the current calendar year.

Section 2: The 4980H(a) Penalty -- Failure to Offer Minimum Essential Coverage

IRC 4980H(a) imposes the Employer Shared Responsibility Payment on an ALE that fails to offer minimum essential coverage (MEC) to at least 95% of its full-time employees (and their dependents), when at least one full-time employee of the ALE receives a premium tax credit (PTC) under IRC 36B for that year. This is the larger penalty, calculated on a per-employee basis across the ALE's entire full-time workforce.

What Counts as Minimum Essential Coverage

Minimum essential coverage (MEC) includes employer-sponsored group health plans that are eligible employer-sponsored plans within the meaning of IRC 5000A(f)(2). A plan satisfies the MEC requirement regardless of whether the coverage is affordable or provides minimum value -- the MEC test is a pure coverage-offer test. Whether the coverage is also affordable and provides minimum value is the 4980H(b) analysis.

The 95% Offer Threshold and the 5% Exception

The 4980H(a) penalty fires only if the ALE fails to offer MEC to at least 95% of its full-time employees (and their dependents) for that month. This means an ALE can fail to offer coverage to a limited number of full-time employees without triggering 4980H(a), provided the number of non-offered employees does not exceed 5% of the full-time workforce (subject to a minimum of five employees). Employers should not treat the 5% exception as a planning threshold; the IRS monitors individual employees' PTC claims and will identify employees for whom no offer was made when those employees enroll in Marketplace coverage.

4980H(a) Penalty Calculation

The 4980H(a) penalty is calculated on a monthly basis and then annualized. The monthly penalty equals the number of full-time employees of the ALE for that month (minus the statutory offset of 30), multiplied by the applicable monthly penalty amount for the year. The annual 4980H(a) penalty is the sum of the monthly penalties for all months in which the failure occurred. The statutory offset of 30 full-time employees reduces the base count from which the penalty is calculated; it is applied at the ALE level, not per entity within a controlled group.

The 4980H(a) monthly penalty amount is indexed annually by IRS guidance. Verify the current year amount at IRS.gov before presenting any calculation to a client or in a Letter 226-J response. Do not state or rely on a specific dollar figure from this guide without that verification.

Section 3: The 4980H(b) Penalty -- Coverage Offered but Not Affordable or Not Minimum Value

IRC 4980H(b) applies when an ALE offers minimum essential coverage to at least 95% of its full-time employees but that coverage is either (a) not affordable, (b) does not provide minimum value, or (c) both -- and at least one full-time employee who was offered coverage that fails the affordability or minimum value test receives a PTC from the Marketplace. Unlike 4980H(a), the 4980H(b) penalty is assessed per affected employee per month, not on the full workforce.

Minimum Value

A plan provides minimum value if it pays for at least 60% of the total allowed costs of benefits provided under the plan (the actuarial value standard). The IRS provides a minimum value calculator, and employers can also use certain safe harbor checklists or obtain an actuarial certification. Coverage that does not provide minimum value fails the 4980H(b) adequacy test even if it is otherwise affordable. Verify the current minimum value standards and tools at IRS.gov.

4980H(b) Penalty Calculation

The 4980H(b) penalty is calculated per affected full-time employee per month. For each calendar month in which a full-time employee receives a PTC and either was not offered coverage or was offered coverage that lacks affordability or minimum value, the ALE owes a monthly penalty for that employee. The monthly 4980H(b) penalty amount per employee is also indexed annually. Verify the current year per-employee amount at IRS.gov. The total annual 4980H(b) liability is the sum of monthly per-employee amounts across all affected employees for all affected months. The 4980H(b) penalty is capped: the aggregate annual 4980H(b) amount cannot exceed the amount that would have been due under 4980H(a) for that year, computed using the same full-workforce method.

Practitioner Note: The PTC Trigger Is the Gating Condition for Both Penalties

Neither 4980H(a) nor 4980H(b) applies unless at least one full-time employee of the ALE actually received a premium tax credit under IRC 36B for the year. An ALE that offered no health coverage at all to any employee owes NO 4980H(a) penalty for a given year if no employee enrolled in Marketplace coverage and received a PTC. However, this is a fact-specific determination: the IRS identifies PTC recipients through Form 1095-A data from the Marketplace. If even one employee received a PTC without the employer's knowledge, the 4980H(a) exposure is triggered. Practitioners advising ALEs should not assume zero exposure simply because the employer believes its employees are not enrolled in Marketplace plans.

Section 4: Affordability Safe Harbors -- W-2, Rate of Pay, and Federal Poverty Line

A plan is affordable under IRC 4980H if the employee's required contribution for self-only coverage does not exceed the applicable affordability percentage of the employee's household income. Because employers do not know their employees' household income, the IRS provides three safe harbors that substitute for household income in the affordability determination. An ALE that satisfies any one of the three safe harbors with respect to a particular employee is not subject to a 4980H(b) penalty for that employee, even if the employee receives a PTC.

The applicable affordability percentage for plan years beginning in 2026 is stated in Rev. Proc. 2025-29. Verify the current year affordability percentage at IRS.gov before advising clients on plan design, premium setting, or safe harbor compliance. The percentage adjusts annually.

Safe Harbor 1: W-2 Wages

Under the W-2 Safe Harbor, coverage is affordable if the employee's required contribution for the lowest-cost self-only plan offering minimum value does not exceed the applicable affordability percentage of the employee's Box 1 W-2 wages for that calendar year. Because Box 1 wages are not known until year-end, using this safe harbor requires a year-end look-back or an estimate-and-true-up approach. A plan that satisfies the W-2 safe harbor in the calendar year is protected even if the employee's actual household income was higher than Box 1 wages.

Safe Harbor 2: Rate of Pay

Under the Rate of Pay Safe Harbor, coverage is affordable if the employee's required contribution does not exceed the applicable affordability percentage of the employee's hourly rate multiplied by 130 hours per month (for hourly employees), or the applicable percentage of the employee's monthly salary (for salaried employees). The Rate of Pay Safe Harbor is generally more administrable than the W-2 safe harbor for employers with a stable workforce, because the premium can be set at the beginning of the plan year based on current rates. However, the rate of pay safe harbor cannot be used for employees whose compensation was reduced during the year if the reduction would make the contribution exceed the threshold.

Safe Harbor 3: Federal Poverty Line

The Federal Poverty Line (FPL) Safe Harbor is the simplest to administer: coverage is affordable if the employee's required contribution for self-only coverage does not exceed the applicable affordability percentage of the federal poverty line for a single individual for the applicable calendar year. Because the FPL amount is published in advance, employers can fix the premium at the start of the plan year with certainty. The FPL safe harbor is the preferred choice for employers who want administrative simplicity and a bright-line safe harbor that is easy to document and defend in a Letter 226-J response. The FPL figure used is the mainland United States figure; Alaska and Hawaii have separate FPL amounts. Verify the current FPL amount and the applicable affordability percentage at IRS.gov.

Practitioner Note: Safe Harbor Selection Must Be Applied Consistently and Documented

An employer may use different affordability safe harbors for different categories of employees (for example, FPL for full-time hourly workers and rate of pay for salaried employees), provided the employer is consistent within each category. The safe harbor election and the underlying data supporting it (W-2 amounts, hourly rates, or FPL reference) must be documented at the plan year level. In a Letter 226-J response, demonstrating safe harbor compliance for the affected employees identified by the IRS is often the most efficient path to penalty abatement. Retain payroll records, plan documents, and premium contribution schedules for each year an ALE is subject to 4980H.

Section 5: Form 1094-C and Form 1095-C Filing Obligations

ALEs are required to file information returns with the IRS and furnish statements to full-time employees annually to report their ACA coverage offers. The annual filing consists of Form 1094-C (the transmittal) and Form 1095-C (the individual employee statements). These forms are the IRS's primary data source for identifying potential ESRP liability and for cross-referencing against Marketplace PTC data. Errors in these forms are the most common source of erroneous Letter 226-J proposals.

Form 1095-C: Employee Statement

Form 1095-C must be furnished to each full-time employee for the calendar year. The form includes:

  • Part I: Employee and employer identifying information.
  • Part II, Line 14 (Offer of Coverage -- the 1A through 1I codes): Reports whether the ALE made an offer of MEC, the type of offer, and whether dependents were included. The B-series offer codes are the most critical field in a Letter 226-J defense: a 1A code (MEC offered and affordable under the FPL safe harbor), 1B code (MEC not offered), 1E code (MEC offered to employee and at least minimum essential coverage offered to dependents), and similar codes directly determine how the IRS calculates potential ESRP exposure. Code errors in Line 14 drive most erroneous 226-J proposals.
  • Part II, Line 15 (Employee Required Contribution): Reports the monthly employee contribution for the lowest-cost self-only minimum value coverage offered. This field is used to test affordability and must reflect the actual premium share, not the plan's full premium.
  • Part II, Line 16 (Safe Harbor Codes -- the 2A through 2I codes): Reports the safe harbor or other relief under which the ALE is protected. A 2C code (employee enrolled in coverage) and a 2E code (multiemployer interim rule relief) are the most commonly applicable. Code 2A (employee not employed for the month) must not be incorrectly applied to months in which the employee was actually a full-time employee of record.
  • Part III: Covered individuals -- used by self-insured employers (or not applicable for fully insured plans where the insurer files the individual coverage information separately).

Form 1094-C: Authoritative Transmittal

Form 1094-C is the transmittal that accompanies the Forms 1095-C filed with the IRS. The ALE must designate one Form 1094-C as the Authoritative Transmittal (checked on Line 19, Part II) that aggregates data across all ALE members and reports aggregate eligibility information. Key sections of the Authoritative Transmittal include Part II (aggregate employer-level data, ALE member count, and the certification of eligibility checkbox for each calendar month), Part III (ALE member information for each ALE member filing their own 1094-C), and Part IV (ALE group member listing). Errors in the certification-of-eligibility checkboxes in Part II are frequently cited in Letter 226-J proposals as evidence that the ALE failed to offer coverage during specific months.

Filing Deadlines and Penalties for Late or Incorrect Filing

The deadline for furnishing Form 1095-C to employees is generally January 31 of the following year, or a date extended by IRS notice. The deadline for filing Forms 1094-C and 1095-C with the IRS is generally February 28 (paper) or March 31 (electronic), also subject to IRS extension. Electronic filing is required for ALEs filing 10 or more information returns. Penalties under IRC 6721 (failure to file with the IRS) and IRC 6722 (failure to furnish to employees) apply for late, incorrect, or missing forms. Verify all current filing deadlines, electronic filing thresholds, and applicable penalty amounts at IRS.gov before each filing season.

Section 6: Letter 226-J Response Workflow

Letter 226-J is the IRS's initial inquiry proposing an ESRP assessment. The IRS generates Letter 226-J by cross-referencing Form 1094-C and 1095-C data with Marketplace enrollment and PTC data from Form 1095-A. The letter identifies the specific tax year, the proposed ESRP amount (broken down by 4980H(a) and 4980H(b) as applicable), and a list of full-time employees the IRS contends received PTCs. Receipt of Letter 226-J is a time-sensitive compliance event: the response window is typically 90 days from the date of the letter.

PRACTITIONER PROTOCOL: LETTER 226-J RESPONSE WORKFLOW

  1. Obtain POA and the full Letter 226-J package. File Form 2848 immediately. The Letter 226-J package includes the cover letter, a summary table of the proposed ESRP by month and by penalty type, and an Employee Premium Tax Credit Listing (similar to Form 14765 format) identifying the specific employees the IRS contends received PTCs. Obtain all attachments.
  2. Verify the response deadline. Confirm the specific response date stated in the letter. Calendar the deadline. If more time is needed, submit a written extension request to the address on the letter before the deadline expires.
  3. Audit the underlying 1094-C and 1095-C filings. Obtain the ALE's original Forms 1094-C and 1095-C for the year at issue. Compare Part II Line 14 offer codes, Line 15 contribution amounts, and Line 16 safe harbor codes for every employee listed in the IRS's employee list. The most common errors: wrong offer code (1H instead of 1A), missing Line 16 safe harbor code, incorrect Line 15 amounts, or employees coded as non-full-time who were actually full-time.
  4. Verify ALE status and the full-time employee count. Confirm the client's ALE status for the year at issue and verify the full-time employee count used in the IRS's 4980H(a) calculation. If the IRS overstated the FTE count, that is a basis for challenging the penalty amount.
  5. Identify mismatched employees in the PTC listing. For each employee in the IRS's listing, determine whether the employee was actually a full-time employee of the ALE for the months listed, whether an offer of coverage was made (and documented), and whether the offer satisfied an affordability safe harbor. Employees who were part-time, seasonal, or already enrolled in employer coverage should be identified for removal from the listing.
  6. Prepare Form 14764 (ESRP Response) and, if applicable, Form 14765 (Employee Premium Tax Credit Listing corrections). Form 14764 is the ALE's formal response to the proposed ESRP. Check the appropriate box (agree, partially agree, or disagree) and include a written explanation with supporting documentation. Form 14765 is used to challenge the IRS's employee list -- for each disputed employee, indicate the correction and provide documentary support (payroll records, offer documentation, enrollment records).
  7. Submit corrected Forms 1094-C and 1095-C if errors are found. If the root cause of the 226-J proposal is a coding error in the original 1095-C filing, prepare corrected forms (marked as corrected) and submit them with the Form 14764 response. Corrected filings that support the ALE's position are among the most effective tools in abatement.
  8. Send the response by the deadline and retain proof of submission. Submit Form 14764 and all supporting documents to the address stated in Letter 226-J. Use certified mail with return receipt, or the IRS's authorized fax or electronic submission option if specified in the letter. Retain a complete copy of everything submitted and the proof of delivery.
  9. Track the IRS's acknowledgment and next communication. After the IRS processes the response, it will send Letter 227 (acknowledging the response and providing a preliminary determination) or a Notice and Demand if the response was rejected. If the IRS proposes a revised ESRP in Letter 227, the ALE has additional appeal rights including pre-assessment review through the IRS Independent Office of Appeals.

Section 7: The Controlled Group Trap -- IRC 414 Aggregation and ALE Status

The controlled group aggregation rules are the most common source of unexpected ALE status. A business owner with multiple entities, a franchisee with several locations organized as separate LLCs, or a professional service firm with a management company affiliate can find that all entities are aggregated into a single ALE under IRC 414, even if each individual entity is well below 50 full-time employees on its own.

Which IRC 414 Rules Apply

Under the ACA regulations implementing IRC 4980H, all employees of a controlled group as determined under IRC 414(b) (controlled groups of corporations), IRC 414(c) (controlled groups of partnerships and proprietorships under common control), IRC 414(m) (affiliated service groups), and IRC 414(o) (other organizations) are treated as employed by a single employer for ALE determination purposes. The IRC 414 attribution and aggregation rules are complex and fact-intensive; the determination requires analysis of ownership percentages, constructive ownership, and the nature of services performed among related entities.

How the 30-Employee Offset Works in a Controlled Group

When the 4980H(a) penalty applies to a controlled group, the 30-employee statutory offset is allocated among the ALE members of the controlled group in proportion to each member's share of the total number of full-time employees of the group. The offset is not separately available to each legal entity; it is shared across the group. Practitioners must compute the controlled group's total penalty first and then allocate both the offset and the resulting penalty among the constituent legal entities.

Practical Steps: Performing the IRC 414 Analysis

  • Obtain a complete entity map for the client, including all legal entities in which the client or any related party holds an ownership interest, directly or constructively.
  • Determine ownership percentages and apply the constructive ownership rules under IRC 318 (for corporations) and IRC 267(c) (for partnerships and LLCs taxed as partnerships) as incorporated into IRC 414(b) and (c).
  • Identify any affiliated service group arrangements under IRC 414(m), particularly where one entity performs management, administrative, or professional services for another.
  • Aggregate the full-time employee and FTE counts across all related entities before concluding whether any individual entity is an ALE or not.
  • Document the analysis in the client file. An ALE that is surprised by a Letter 226-J because its adviser never identified the controlled group relationship has no factual basis to challenge the underlying ALE determination.

Section 8: 4980H(a) vs. 4980H(b) -- Side-by-Side Comparison

The table below compares the key attributes of the two IRC 4980H penalty provisions. Penalty amounts are indexed annually; verify current year figures at IRS.gov before relying on them in any engagement.

Attribute IRC 4980H(a) IRC 4980H(b)
Trigger condition ALE fails to offer MEC to at least 95% of full-time employees (and dependents) ALE offers MEC but it is not affordable or does not provide minimum value
PTC requirement At least one full-time employee must receive a PTC for the year The specific employee who was not offered adequate coverage must receive a PTC
Penalty base All full-time employees of the ALE (minus the 30-employee offset) Only the specific full-time employees who received a PTC and lacked adequate coverage
Monthly calculation (Total full-time employees minus 30) x monthly per-employee amount Number of affected employees x monthly per-employee amount for that month
Relative penalty amount Generally higher per year (whole workforce basis) Generally lower per year (limited to affected employees only)
Annual cap No separate cap; limited by the workforce count for the year Capped at the 4980H(a) amount that would have applied for the same year
Who is counted Full-time employees only (FTEs are excluded from penalty base) Full-time employees only (the affected employees who received PTCs)
Can both apply simultaneously? No: 4980H(a) and 4980H(b) are mutually exclusive per employee per month No: if 4980H(a) applies, 4980H(b) cannot also apply for the same month
Primary defense Demonstrate that a qualifying offer of MEC was made to at least 95% of full-time employees Demonstrate affordability under an IRS safe harbor or that coverage provided minimum value
How to avoid Offer MEC to at least 95% of all full-time employees (and their dependents) each month Ensure the lowest-cost self-only plan option satisfies the applicable affordability percentage and the 60% minimum value standard

Frequently Asked Questions: IRC 4980H Employer Mandate

What is the IRC 4980H employer mandate and who does it apply to?

IRC 4980H imposes the ACA Employer Shared Responsibility Payment (ESRP) on Applicable Large Employers (ALEs) that fail to offer adequate health coverage to full-time employees. An ALE is an employer that averaged at least 50 full-time employees (including full-time equivalents) during the preceding calendar year. ALE status is determined at the controlled group level under IRC 414. The mandate has two separate penalty tracks: IRC 4980H(a) for failing to offer minimum essential coverage to at least 95% of full-time employees, and IRC 4980H(b) for offering coverage that is not affordable or does not provide minimum value. Verify current requirements at IRS.gov.

How does a practitioner determine whether a client is an Applicable Large Employer?

ALE status for a given year is based on the average number of full-time employees (30 or more hours per week, or 130 hours per month) plus full-time equivalents (part-time hours aggregated and divided by 120) employed during the preceding calendar year. If the combined average was 50 or more, the employer is an ALE. All members of a controlled group under IRC 414(b), (c), (m), or (o) are treated as a single employer for ALE determination. A seasonal employee exception applies if the workforce exceeded 50 employees for no more than 120 days and the excess was attributable to seasonal workers. Confirm all calculations and exceptions at IRS.gov.

What is the difference between the 4980H(a) penalty and the 4980H(b) penalty?

IRC 4980H(a) applies when an ALE fails to offer minimum essential coverage to at least 95% of its full-time employees, and at least one full-time employee receives a premium tax credit. The 4980H(a) penalty is calculated on all full-time employees minus the 30-employee offset. IRC 4980H(b) applies when MEC is offered but is either not affordable or lacks minimum value, and the specific employee who received the inadequate offer actually received a PTC. The 4980H(b) penalty is per affected employee per month, generally lower per year than 4980H(a). The two are mutually exclusive per employee per month. Verify current penalty amounts at IRS.gov.

What are the three affordability safe harbors and which is simplest to use?

The three affordability safe harbors are: (1) W-2 Safe Harbor, where the required employee contribution does not exceed the applicable affordability percentage of Box 1 W-2 wages; (2) Rate of Pay Safe Harbor, where the contribution does not exceed the applicable percentage of 130 hours times the hourly rate (or monthly salary for salaried employees); and (3) Federal Poverty Line Safe Harbor, where the contribution does not exceed the applicable percentage of the FPL for a single individual. The FPL safe harbor is simplest to administer because the premium can be fixed at plan year start without later adjustment. The 2026 affordability percentage is per Rev. Proc. 2025-29; verify at IRS.gov before advising.

What is Letter 226-J and how should a practitioner respond?

Letter 226-J is the IRS's notice of a proposed Employer Shared Responsibility Payment. It includes a proposed ESRP amount by year, a breakdown of the 4980H(a) and 4980H(b) components, and a listing of full-time employees the IRS believes received PTCs. Employers typically have 90 days from the date of the letter to respond using Form 14764 (ESRP Response) and, if contesting the employee list, Form 14765 (Employee Premium Tax Credit Listing corrections). A complete and timely response is critical: no response results in the IRS issuing a Notice and Demand converting the proposal to an assessed liability. Verify all response requirements and deadlines in the specific letter received.

Can an employer be liable under both 4980H(a) and 4980H(b) for the same employee?

No. IRC 4980H(a) and IRC 4980H(b) are mutually exclusive per employee per month. If 4980H(a) applies for a given employee in a given month (because no MEC was offered), 4980H(b) cannot also apply for the same employee and month. However, different subsections can apply to different employees in the same year: an employer might face 4980H(a) for employees who received no offer and 4980H(b) for employees who received an unaffordable or non-minimum-value offer. Verify the interaction of the two subsections and the penalty calculation rules at IRS.gov before advising.

How does controlled group aggregation affect ALE status and 4980H liability?

Under IRC 414(b), (c), (m), and (o), all members of a controlled group or affiliated service group are treated as a single employer for ALE determination. A business with 30 full-time employees under common ownership with another entity having 25 full-time employees is treated as a single 55-employee ALE. Each legal entity within the controlled group is separately responsible for its own ESRP assessment, but ALE status is determined at the aggregated level. The 30-employee statutory offset is shared across the controlled group, not available separately to each member. Practitioners advising multi-entity clients must perform the IRC 414 aggregation analysis first. Confirm all aggregation rules at IRS.gov.

Did the One Big Beautiful Bill Act change IRC 4980H?

No. The One Big Beautiful Bill Act (OBBBA) did not amend IRC 4980H. The employer shared responsibility framework, penalty structure, and ALE threshold remain as established under the ACA. The 2026 affordability percentage was updated by Rev. Proc. 2025-29. Penalty amounts under 4980H(a) and 4980H(b) are indexed annually by IRS guidance; verify current year figures at IRS.gov. Practitioners should also verify whether OBBBA or subsequent legislation has affected the premium tax credit rules under IRC 36B, because PTC eligibility triggers both 4980H penalties. Confirm current law at IRS.gov before advising on ACA compliance for any open year.