What Is a 1095-C Form? The Complete 2026 Guide for Employees and Employers

Form 1095-C is an IRS information return called “Employer-Provided Health Insurance Offer and Coverage.” Applicable Large Employers (ALEs), businesses with 50 or more full-time or full-time-equivalent employees, send this form to eligible employees and file it with the IRS every year. It documents exactly what health coverage was offered, to which employee, for which months, and at what cost, regardless of whether the employee actually signed up.

If a 1095-C landed in your mailbox and you’re not sure why, or you’re an employer trying to figure out whether you owe one to your team, this guide walks through what the 1095-C tax form is for, who has to send it, whether you need it to file your taxes, what the confusing codes mean, and every 2026 deadline that applies. Our team at KMK Ventures handles ACA reporting for outsourced payroll management clients every filing season, so this is written from the compliance side, not just the tax-form side.

Form 1095-C at a Glance

What Is Form 1095-C Used For?

Form 1095-C exists to enforce the ACA’s employer mandate. The IRS uses it to check two things every year: did a large employer offer affordable, minimum-value coverage to enough of its full-time workforce, and did any employee who wasn’t offered adequate coverage go on to claim a subsidized Marketplace plan. If the answer to the second question is yes, the employer can owe an Employer Shared Responsibility Payment.

For the employee, the 1095-C is simply a record. It’s not a bill, and it’s not proof that you have coverage right now. It’s proof of what your employer made available to you during a specific tax year.

Who Has to File Form 1095-C?

Only employers the IRS classifies as Applicable Large Employers (ALEs) are required to issue Form 1095-C. You’re an ALE if your business averaged 50 or more full-time employees (full-time equivalents included) during the prior calendar year. Companies below that threshold generally don’t have to send this form; smaller, self-insured employers use Form 1095-B instead.

For businesses managing benefits and payroll internally, ACA reporting is one more year-end compliance task sitting next to W-2s, 1099s, and quarterly filings. Getting employee counts, coverage offers, and affordability math right the first time is what keeps a company off the IRS’s Letter 226-J list. This is exactly the kind of detail-heavy, deadline-driven work our outsourced tax services and bookkeeping teams handle for clients so nothing slips.

What Information Is on a 1095-C Form?

The form has three parts:

• Part I: Employee and Employer Information. Names, addresses, and identifying numbers for both the employee and the ALE.
• Part II: Employee Offer and Coverage. The core of the form. Line 14 uses a code to describe the type of coverage offered each month. Line 15 shows the employee’s monthly share of the lowest-cost, self-only premium available. Line 16 uses a code explaining which “safe harbor” the employer relied on to meet ACA affordability rules that month.
• Part III: Covered Individuals. Completed only when the employer’s plan is self-insured. It lists everyone actually enrolled (employee, spouse, dependents) and the months each person had coverage.

Think of Part II as “what was offered” and Part III as “who was actually covered.” They can tell different stories: an employee can decline coverage entirely and still have Part II filled out in full.

Form 1095-C Line 14 and Line 16 Codes, Explained

These codes confuse almost everyone who reads them, including new HR staff. Here’s the short version, pulled from the IRS instructions for Forms 1094-C and 1095-C.

Line 14 (Series 1): what was offered

Line 16 (Series 2): the employer’s explanation

If line 14 shows 1B, 1C, 1E, 1J, 1K, 1L–1U, or similar, line 15 must show a dollar amount. Codes 1A and 1G leave line 15 blank because affordability is already assumed or not applicable. Getting these three lines to agree with each other, month by month, is the single most common source of IRS rejection notices. That’s why many employers run a second set of eyes over the codes through a tax planning and advisory partner before filing.

Form 1095-C vs. 1095-A vs. 1095-B

The three 1095 forms get mixed up constantly:

• Form 1095-A comes from the Health Insurance Marketplace if you bought a plan through healthcare.gov or a state exchange. It’s the one you may actually need to reconcile premium tax credits on your return.
• Form 1095-B comes from insurance carriers or from smaller, self-insured employers, confirming who had minimum essential coverage and for which months.
• Form 1095-C comes from large employers and documents what coverage was offered, whether or not the employee used it.

Do You Need Form 1095-C to File Your Taxes?

This is the question most employees actually want answered: no, you don’t need to attach Form 1095-C to your federal tax return, and in most cases you won’t enter anything from it on Form 1040. Since the federal individual mandate penalty was reduced to $0, the IRS no longer requires proof of coverage on your federal return.

Still, hold on to it. A few situations where it matters:

• You live in a state with its own individual mandate (Massachusetts, New Jersey, California, Rhode Island, or Washington, D.C.), where your state return may ask about coverage.
• You also received a Form 1095-A because you were on a Marketplace plan for part of the year. The 1095-C helps confirm you weren’t also eligible for employer coverage during those same months, which affects premium tax credit reconciliation.
• The IRS or a state tax agency questions your coverage status and asks for documentation.

File your return normally, keep the 1095-C with your tax records for at least three years, and only pull it out if a state return or a Marketplace credit calculation asks for it.

1095-C Instructions: How Employers Fill It Out

If you’re the one issuing the form, here’s the process in five steps:

1. Confirm ALE status by averaging full-time and full-time-equivalent employees from the prior calendar year.
2. Track monthly coverage offers for every full-time employee, including whether the plan was affordable under one of the IRS safe harbors (Federal Poverty Line, Rate of Pay, or W-2 wages).
3. Assign the correct Line 14 and Line 16 codes for each month using the tables above. Mismatched codes are the top reason employers get an IRS notice.
4. Complete Part III if your plan is self-insured, listing every covered individual and their months of coverage.
5. Furnish employee copies and file Form 1094-C (the transmittal summary) with all 1095-Cs attached.

When Is Form 1095-C Due in 2026?

For the 2025 tax year (filed in 2026):

A newer IRS rule also lets employers skip automatically mailing every employee a copy, as long as the company posts a clear, easy-to-find notice on its benefits website stating employees can request a copy, then furnishes it within 30 days of the request, or by January 31, 2026, whichever is later. Employers still need to track those requests carefully; missing a requested copy carries the same penalty exposure as missing the original deadline.

Employers filing 10 or more information returns total (W-2s, 1099s, and 1095-Cs combined) must file electronically, and nearly every ALE falls into this bucket. Since the IRS AIR e-filing system closes for its annual maintenance window in December and doesn’t reopen until early January, employers who wait until the last week of March to file often run out of runway to fix rejected submissions. Building this into your broader important 2026 tax dates calendar avoids that scramble.

What Happens If an Employer Doesn’t File Form 1095-C?

Missing or botching a 1095-C filing exposes an employer to two separate categories of penalty:

1. Employer Shared Responsibility Payments (Section 4980H)

• 4980H(a): For 2026, this penalty is $3,340 per year ($278.33/month), assessed on the full-time headcount minus the first 30 employees, and applies if an ALE fails to offer minimum essential coverage to at least 95% of full-time employees and their dependents, and at least one employee gets subsidized Marketplace coverage.
• 4980H(b): For 2026, this penalty is $5,010 per year ($417.50/month) per affected employee, and applies if coverage was offered but wasn’t affordable or didn’t provide minimum value for the specific employee who received a subsidy.

2. Information return penalties (Sections 6721/6722) for filing late, filing on paper when e-filing was required, or sending incorrect or incomplete forms. These penalties are per form and per employee, so they compound quickly for a mid-size workforce.

Because a single coding mistake can trigger a Letter 226-J months or years after the fact, most growing companies pair year-end ACA reporting with a review from their tax planning and advisory team or their full-scale outsourced accounting provider rather than handle it in-house with a spreadsheet.