Form 1094-C: Filing Requirements, Deadlines, and Penalties

Form 1094-C is the transmittal cover sheet that an Applicable Large Employer files with the IRS to summarize the Form 1095-C returns it submits for each employee, and the filing requirements for Form 1094-C reach any employer that averaged at least 50 full-time employees, including full-time equivalents, during the prior calendar year. The obligation lives in Sections 6055 and 6056 of the Internal Revenue Code and still applies even though the individual mandate penalty has been $0 since 2019.¹ Miss the deadline for tax year 2025 returns and you can face penalties of up to $340 per return, with a calendar-year cap above $4 million for larger organizations.²

Who Has to File Form 1094-C

Form 1094-C is for Applicable Large Employers, meaning organizations that employed an average of at least 50 full-time employees on business days during the preceding calendar year. Full-time equivalents count toward the 50. A business with 40 full-time workers and enough part-time hours to produce 10 or more full-time equivalents is an ALE and must file.³

The full-time equivalent math has two steps. Add up the total hours of service for all non-full-time employees in a given month, capping any single employee at 120 hours. Divide that total by 120. That gives you the full-time equivalent count for the month.⁴ Average those monthly counts across the calendar year, add the average monthly full-time headcount, and compare the sum against 50.

One boundary worth flagging. If you are a small employer (fewer than 50 full-time employees, so not an ALE) that sponsors a self-insured group health plan, you still have a reporting obligation under Section 6055, but you file Form 1094-B and Form 1095-B rather than the 1094-C/1095-C pair.⁵ Small employers with fully insured plans do not file either transmittal themselves; the insurance carrier handles it.

What Goes on the Form

Form 1094-C collects employer-level data in three parts, and a few fields carry more weight than the rest.

Part I asks for the legal name of the ALE Member, its Employer Identification Number, the principal office address, and a contact person. The EIN must match IRS records exactly, and it must be the ALE Member’s own EIN, not that of a payroll agent or subsidiary.⁶

Line 18 reports the total number of Forms 1095-C included with the transmittal. The IRS reconciles this count against what it actually receives, so an incorrect number flags the filing. Line 19 is the Authoritative Transmittal checkbox. Each ALE Member designates exactly one Form 1094-C as the Authoritative Transmittal, which tells the IRS that this filing carries the aggregate employer-level data for the entity. If you submit multiple 1094-C forms because separate divisions transmit separately, only one gets that designation.⁶

Part III, labeled “ALE Member Information—Monthly,” breaks the reporting year into 12 rows. For each month you report whether minimum essential coverage was offered to at least 95 percent of full-time employees in Column (a) and the Section 4980H full-time employee count in Column (b).⁶ This is the data the IRS cross-references when deciding whether to assess an employer shared responsibility payment, so accuracy here matters beyond the transmittal itself.

How to File

Nearly every ALE files electronically. Since tax year 2023, any entity filing 10 or more information returns in aggregate across all types (W-2s, 1099s, 1095-Cs, and the rest combined) must file them electronically.⁷ An employer with 50 or more full-time employees will hit 10 returns virtually every time.

Electronic filing goes through the ACA Information Returns (AIR) system, not the FIRE system used for most other information returns. Before your first submission you need to apply for an ACA-specific Transmitter Control Code through the IRS and complete a one-time communication test with AIR.⁸ Many employers outsource this to payroll vendors or third-party transmitters who already hold a TCC. AIR sends back an acknowledgment after each transmission; if the status comes back “Accepted with Errors,” file corrections promptly.

Paper filing is available if you file fewer than 10 total information returns, with the mailing address listed in the form instructions. Few ALEs qualify, given the 50-employee threshold that puts them in the reporting system to begin with.

Deadlines for Tax Year 2025 Returns

Three separate dates cover three different obligations.

Furnish Form 1095-C to employees by March 2, 2026. The IRS permanently extended this from January 31 to 30 days after January 31.
Paper filing with the IRS is normally due February 28. In 2026 that falls on a Saturday, so the deadline shifts to Monday, March 2, 2026.
Electronic filing with the IRS is due March 31, 2026.⁶

If you need more time to file with the IRS, submit Form 8809 before the original deadline for an automatic 30-day extension. The extension covers only the IRS filing; it does not push back the date for furnishing statements to employees.⁹ Form 8809 can go through the FIRE system or on paper.

Penalties for Late or Incorrect Filings

Two penalty regimes can hit the same employer at the same time. Sections 6721 and 6722 punish failures to file correct returns with the IRS and failures to furnish correct statements to employees. Section 4980H imposes the employer shared responsibility payment when coverage falls short.

Information Return Penalties

For returns due in 2026, the per-return amount depends on how quickly you correct it:²

Corrected within 30 days of the deadline: $60 per return, calendar-year maximum $683,000 ($239,000 for small businesses with average gross receipts of $5 million or less).
Corrected after 30 days but by August 1: $130 per return, maximum $2,049,000 ($683,000 for small businesses).
Filed after August 1 or never filed: $340 per return, maximum $4,098,500 ($1,366,000 for small businesses).
Intentional disregard: $680 per return with no cap.¹⁰

The caps look high in the abstract but fill quickly. An ALE with 500 full-time employees that misses the deadline entirely faces $170,000 in baseline exposure on the 1095-C side alone, before the matching 1094-C transmittal penalty.

Employer Shared Responsibility Payments

The IRS uses Part III monthly data on Form 1094-C and the offer codes on each Form 1095-C to decide whether an ALE owes a payment under Section 4980H. Two tiers apply for 2026:¹¹

Section 4980H(a): if you fail to offer minimum essential coverage to at least 95 percent of your full-time employees and any one of them receives a premium tax credit through the Marketplace, the annual payment is $3,340 per full-time employee, minus the first 30.
Section 4980H(b): if you do offer coverage but it is unaffordable or fails to meet minimum value, the payment is $5,010 for each full-time employee who actually receives a Marketplace premium tax credit.

Not filing at all does not avoid the assessment. It just means the IRS has no evidence of an offer and may presume none was made.

Fixing Errors After You File

When you find an error on a filed Form 1094-C, submit a corrected return as soon as possible. For the Authoritative Transmittal, file a standalone, fully completed Form 1094-C with the CORRECTED checkbox marked and the right information entered. Do not attach any Forms 1095-C to the corrected transmittal; corrections to individual employee records go on corrected Forms 1095-C filed separately.⁶

Speed pays. Fixing an error within 30 days of the original deadline cuts the per-return penalty from $340 to $60. Correcting by August 1 keeps it at $130. After August 1 the full penalty applies and the only remaining argument is reasonable cause.²

1
Internal Revenue Service. Questions and Answers on the Individual Shared Responsibility Provision
2
Internal Revenue Service. Information Return Penalties
3
Office of the Law Revision Counsel. 26 US Code 4980H – Shared Responsibility for Employers Regarding Health Coverage
4
Internal Revenue Service. Determining if an Employer Is an Applicable Large Employer
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Internal Revenue Service. Instructions for Forms 1094-B and 1095-B
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Internal Revenue Service. Instructions for Forms 1094-C and 1095-C
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Internal Revenue Service. Topic No. 801, Who Must File Information Returns Electronically
8
Internal Revenue Service. Affordable Care Act Information Returns (AIR)
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Internal Revenue Service. About Form 8809, Application for Extension of Time to File Information Returns
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Internal Revenue Service. 20.1.7 Information Return Penalties
11
Internal Revenue Service. Affordable Care Act Tax Provisions for Employers