Understanding Form 1095-C Part III for Self-Insured Employers: Complete Guide

Introduction: The Critical Question About 1095-C Part III Self-Insured Reporting

If you operate a self-insured health plan and are wondering "do I need to complete Part III of 1095-C for my self-insured plan," the short answer is almost certainly yes. Understanding 1095-C Part III self-insured requirements is one of the most common compliance challenges facing employers who fund their own health coverage. Part III is specifically designed for self-insured employers to report covered individuals, and completing it correctly is essential for avoiding IRS penalties and ensuring your employees have proper documentation of their health coverage.

The Affordable Care Act (ACA) created different reporting obligations for self-insured employers compared to those who purchase coverage from insurance companies. When you self-insure, you serve as both the employer offering coverage AND the entity providing minimum essential coverage (MEC). This dual role means you must complete all three parts of Form 1095-C, including the often-confusing Part III, which requires detailed information about every person enrolled in your health plan. Missing this requirement or completing it incorrectly can result in penalties up to $330 per form for failure to file correct information returns.

This comprehensive guide answers the question of when and how to complete 1095-C Part III for self-insured health plans. We will explain exactly who must complete Part III, what information is required, how to handle special situations like COBRA continuation and mid-year coverage changes, and how to avoid the most common mistakes that trigger IRS notices. Whether you are an HR director, benefits administrator, or third-party administrator managing self-insured plans, this guide provides the definitive resource for understanding your Part III obligations.

The stakes are significant. Self-insured employers who fail to complete Part III correctly face both information return penalties (for incorrect forms filed with the IRS) and furnishing penalties (for incorrect forms provided to employees). With potential penalties exceeding $3.9 million annually for large employers, getting Part III right is not optional. Let us dive into everything you need to know about 1095-C Part III self-insured compliance.

What Is Part III of Form 1095-C and Why Does It Matter?

The Structure of Form 1095-C

Before addressing the Part III question, it helps to understand how Form 1095-C is structured. The form has three distinct parts, each serving a different purpose under the ACA's reporting framework:

Part I: Employee Information

  • Contains the employee's name, Social Security Number, and address
  • Includes the employer's information (name, EIN, address, contact)
  • This section is completed for ALL employees receiving a 1095-C, regardless of plan type

Part II: Coverage Offer and Employee Share of Lowest Cost Monthly Premium

  • Reports what coverage was offered to the employee each month
  • Uses Line 14 codes to indicate the type of coverage offer
  • Shows the employee's required premium contribution (Line 15)
  • Reports Line 16 safe harbor codes when applicable
  • This section is completed by ALL Applicable Large Employers, both fully-insured and self-insured

Part III: Covered Individuals

  • Reports who was actually enrolled in the employer's self-insured health plan
  • Requires name, SSN (or DOB), and covered months for each enrolled individual
  • Includes the employee (if enrolled), spouse, and dependent children
  • This section is ONLY completed by self-insured employers

The key distinction is that Part III is a self-insured employer exclusive. Fully-insured employers leave Part III blank because their insurance company separately files Form 1095-B to report enrolled individuals. But when you are self-insured, there is no insurance company to file that report, so you must complete 1095-C Part III to document who had minimum essential coverage under your plan.

The Legal Basis for Part III Reporting

The requirement to complete Part III stems from IRC Section 6055, which mandates that providers of minimum essential coverage report coverage to the IRS and furnish statements to covered individuals. When you operate a self-insured health plan, you are the coverage provider under Section 6055. This creates the 1095-C Part III self-insured requirement.

Specifically, Section 6055 requires reporting of:

  • The name, address, and TIN of the coverage provider (your company)
  • The name, address, and TIN of each covered individual
  • The months during which the individual was covered

For self-insured ALEs, the IRS combined this Section 6055 requirement with the Section 6056 requirement (reporting coverage offers) into a single Form 1095-C with Part III serving the Section 6055 function. This saves self-insured employers from filing two separate forms (1095-C and 1095-B) for each employee.

When Do You Need to Complete Part III? A Definitive Guide

The Simple Rule: Self-Insured ALEs Complete Part III

The fundamental rule for 1095-C Part III self-insured reporting is straightforward: if you are an Applicable Large Employer (ALE) with a self-insured health plan, you must complete Part III for any employee who has covered individuals enrolled in that plan. Let us break down each component:

You are an ALE if:

  • You employed an average of 50 or more full-time equivalent employees during the prior calendar year
  • Full-time employees (30+ hours/week) count as one each
  • Part-time employee hours are totaled and divided by 120 to get FTE equivalents
  • Use the FTE calculation to determine ALE status

You have a self-insured plan if:

  • Your company pays health claims directly (often through a TPA) rather than paying premiums to an insurer
  • Your monthly health costs vary based on actual claims rather than fixed premium amounts
  • You may have stop-loss insurance for catastrophic claims, but this does not change self-insured status
  • Level-funded plans may be self-insured depending on their structure (consult your benefits advisor)

You complete Part III when:

  • Any individual is enrolled in the self-insured plan under that employee's coverage
  • This includes the employee themselves if enrolled
  • This includes any covered spouse or dependent children
  • This includes COBRA continuees under the employee's original enrollment

When Part III Is Left Blank

There are specific situations where Part III remains blank even for self-insured employers:

Scenario 1: Fully-insured employer

If your health plan is fully-insured (you pay fixed premiums to an insurance company), you do NOT complete Part III. The insurance company files Form 1095-B to report enrolled individuals instead.

Scenario 2: Employee waives all coverage

If an employee declines coverage for themselves and does not enroll any dependents, Part III is left blank. There are no covered individuals to report. However, Part II must still show the appropriate offer codes indicating coverage was offered but declined.

Scenario 3: Mixed coverage (uncommon)

Some employers offer both self-insured and fully-insured options. If an employee enrolls in the fully-insured option, Part III is blank for that employee (the insurer handles 1095-B reporting). Only employees enrolled in the self-insured option have Part III completed.

Decision Matrix: Do You Complete Part III?

Employer Type Plan Type Employee Enrollment Status Complete Part III?
ALE (50+ FTE) Self-Insured Employee enrolled (with or without dependents) YES
ALE (50+ FTE) Self-Insured Employee waived, but dependents enrolled YES (list enrolled dependents only)
ALE (50+ FTE) Self-Insured Employee and all dependents waived coverage NO (leave blank)
ALE (50+ FTE) Fully-Insured Any status NO (insurer files 1095-B)
Small Employer (under 50 FTE) Self-Insured Any enrollment NO (file 1095-B instead of 1095-C)

Important note for small self-insured employers: If you have fewer than 50 FTEs but operate a self-insured plan, you are NOT an ALE and do NOT file Form 1095-C. Instead, you file Form 1095-B to report your covered individuals. The 1095-C Part III self-insured requirement applies only to ALEs.

How to Complete Part III of Form 1095-C: Step-by-Step Instructions

Step 1: Identify All Covered Individuals

For each employee receiving a Form 1095-C, determine who was enrolled in your self-insured plan at any point during the calendar year. Include:

  • The employee: If they enrolled in coverage (rather than waiving)
  • Spouse: A legal spouse under federal law who is enrolled in coverage
  • Dependent children: Generally children under age 26 (or as defined by your plan) who are enrolled
  • Other eligible individuals: Depending on plan design, this might include domestic partners or other dependents

Do NOT include individuals who were offered coverage but did not enroll. Part III reports only those who actually had coverage under your plan.

Step 2: Gather Required Data for Each Covered Individual

For each person identified in Step 1, collect the following information:

Full Legal Name:

  • First name, middle initial (if available), and last name
  • The name should match what appears on the individual's Social Security card
  • For married spouses, use their current legal name (not maiden name, unless that is their legal name)

Social Security Number (SSN):

  • 9-digit SSN without dashes (for electronic filing)
  • If SSN is unavailable, you may use date of birth instead (see below)
  • Make reasonable efforts to obtain SSNs before using the DOB alternative

Date of Birth (alternative to SSN):

  • Use when SSN is genuinely unavailable (newborns, uncooperative dependents, etc.)
  • Format: MMDDYYYY for electronic filing
  • The IRS prefers SSN; using DOB may trigger follow-up inquiries

Step 3: Determine Covered Months

For each covered individual, determine which months they had coverage under your self-insured plan. The IRS applies a "first of the month" rule:

  • If coverage was in effect on the first day of a month, that month is a covered month
  • If coverage began mid-month (e.g., effective March 15), the first covered month is the following month (April in this example)
  • If coverage ended mid-month (e.g., terminated June 20), that month still counts as covered because coverage existed on June 1

Special situations for covered months:

  • Newborns: If a baby is born mid-month and coverage is effective from birth, check covered months based on when coverage began under your plan terms
  • COBRA: Continue checking covered months for as long as the individual is enrolled and paying COBRA premiums
  • Retroactive coverage: If coverage is added retroactively (e.g., newborn added effective date of birth), include all covered months retroactively

Step 4: Enter Data on the Form

Part III of Form 1095-C has space for six covered individuals. For each person, enter:

  • Column (a) - Name: Enter the full name of the covered individual
  • Column (b) - SSN or DOB: Enter either the 9-digit SSN or, if unavailable, the date of birth
  • Column (c) - Covered all 12 months: Check this box if the individual was covered for the entire year. When this is checked, you do not need to check individual month boxes
  • Columns for Jan-Dec: If not covered all 12 months, check each box for months the individual had coverage

Step 5: Handle More Than Six Covered Individuals

If an employee has more than six covered individuals (including themselves), you must use continuation sheets:

  • Generate additional Forms 1095-C for the same employee
  • On continuation forms, complete Part III only
  • Leave Parts I and II blank on continuation forms
  • Include the employee's identifying information at the top of each continuation

This situation is uncommon but can occur with blended families or employees with many dependents.

Real-World Scenarios for 1095-C Part III Self-Insured Reporting

Scenario 1: Standard Family Enrollment All Year

Situation: Robert has been employed at your company all year. He enrolled himself, his spouse Maria, and their two children (ages 10 and 14) in your self-insured health plan effective January 1. All four remained enrolled through December 31.

Part III Completion:

  • Row 1: Robert Smith | XXX-XX-XXXX | Check "Covered all 12 months"
  • Row 2: Maria Smith | XXX-XX-XXXX | Check "Covered all 12 months"
  • Row 3: Child 1 Name | XXX-XX-XXXX | Check "Covered all 12 months"
  • Row 4: Child 2 Name | XXX-XX-XXXX | Check "Covered all 12 months"

Scenario 2: New Hire with Mid-Year Enrollment

Situation: Jennifer was hired on April 10 and enrolled in your self-insured plan effective May 1, covering herself only (no dependents). She remained enrolled through year-end.

Part II Implications:

  • January-April: Code 1H (no offer) on Line 14, Code 2D (not employed) or 2B (not full-time) on Line 16
  • May-December: Code 1E or appropriate offer code on Line 14, applicable safe harbor on Line 16

Part III Completion:

  • Row 1: Jennifer Johnson | XXX-XX-XXXX | Check boxes for May through December (8 months)
  • Do NOT check January through April (no coverage those months)

Scenario 3: Employee Waives, Children Enrolled

Situation: Michael is covered under his spouse's employer plan and waives your coverage. However, your plan allows him to enroll his three children without enrolling himself. The children have been enrolled all year.

Part II Implications:

  • Line 14 shows coverage was offered (e.g., Code 1E for MEC plus dependents)
  • Line 15 shows the employee's share of premium for self-only coverage
  • Line 16 shows appropriate safe harbor code

Part III Completion:

  • Michael is NOT listed (he waived coverage and is not enrolled)
  • Row 1: Child 1 Name | XXX-XX-XXXX | Check "Covered all 12 months"
  • Row 2: Child 2 Name | XXX-XX-XXXX | Check "Covered all 12 months"
  • Row 3: Child 3 Name | XXX-XX-XXXX | Check "Covered all 12 months"

Scenario 4: COBRA Continuation After Termination

Situation: David terminated employment on June 30, ending his active employee coverage. He elected COBRA continuation for himself and his family. He paid premiums through October, then let COBRA lapse.

Part II Implications:

  • January-June: Appropriate offer codes for active employment
  • July-December: Code 1H (no offer of employer-sponsored coverage) on Line 14, Code 2A (not employed) on Line 16

Part III Completion:

  • David and family members: Check boxes for January through October
  • Do NOT check November and December (coverage had lapsed)
  • COBRA coverage IS reported in Part III because they were still covered under your self-insured plan

Scenario 5: Newborn Added Mid-Year

Situation: Sarah has been enrolled all year with her spouse. In September, they have a baby who is added to coverage effective from the date of birth (September 15). The baby does not yet have a Social Security Number at the time of ACA filing.

Part III Completion:

  • Row 1: Sarah | XXX-XX-XXXX | Check "Covered all 12 months"
  • Row 2: Spouse | XXX-XX-XXXX | Check "Covered all 12 months"
  • Row 3: Baby's Name | DOB: 09152025 | Check boxes for October, November, December (coverage started October 1 under the first-of-month rule, unless your plan provides coverage from birth date, in which case include September if coverage was effective September 1)

Note: For newborns, if your plan provides immediate coverage from birth and the baby was born before the 1st, coverage might be considered effective the 1st of that month. Consult your plan documents and TPA for specific guidance.

Common Mistakes to Avoid with 1095-C Part III Self-Insured Reporting

Mistake 1: Leaving Part III Blank for Self-Insured Plans

This is the most fundamental error. Some employers complete Parts I and II correctly but forget that self-insured status requires Part III. Every self-insured ALE must complete Part III when individuals are enrolled. Leaving it blank when coverage was provided constitutes an incomplete form subject to penalties.

Mistake 2: Including Individuals Who Were Offered But Not Enrolled

Part III reports only actual enrollment, not coverage offers. If an employee was offered coverage for their family but only enrolled themselves, do not list the spouse or children in Part III. Only those who actually enrolled appear in Part III.

Mistake 3: Incorrect SSN or Name Formatting

Common formatting issues include:

  • Including dashes in SSNs (should be 9 digits with no punctuation for e-filing)
  • Nicknames instead of legal names (use "William" not "Bill" if William is the legal name)
  • Outdated names (use current legal name, not maiden name)
  • Transposed digits in SSNs

Mistake 4: Wrong Coverage Months

Remember the first-of-month rule. If coverage became effective on March 15, the first covered month is April (because coverage was not in effect on March 1). Many employers incorrectly report March as covered when it should not be.

Mistake 5: Omitting COBRA Enrollees

Former employees on COBRA are still covered under your self-insured plan. They must appear in Part III for the months they are enrolled and paying premiums. This is true even though they are no longer active employees and you report "no offer" in Part II.

Mistake 6: Not Using Continuation Forms for Large Families

If an employee has more than six covered individuals, you must use additional 1095-C forms as continuation sheets. Simply omitting covered individuals is not acceptable and results in incomplete reporting.

Mistake 7: Confusing 1095-C Part III with Form 1095-B

Some employers try to file both 1095-C (with Part III) and a separate 1095-B for the same self-insured coverage. This is incorrect. For self-insured ALEs, 1095-C Part III serves the function of 1095-B. Do not file both forms; use only 1095-C with Part III completed.

IRS Penalties for Part III Non-Compliance

Information Return Penalties

Failure to file correct Forms 1095-C (including Part III) or furnish correct copies to employees triggers IRS penalties. For tax year 2025 (filed in 2026), penalties are:

Timing of Correct Filing Penalty Per Form Annual Cap
Filed correctly within 30 days of deadline $60 $664,500
Filed correctly more than 30 days late but by August 1 $130 $1,993,500
Filed after August 1 or not filed at all $330 $3,987,000
Intentional disregard of requirements $660 minimum No cap

These penalties apply separately for failure to file with the IRS and failure to furnish statements to employees. An employer who fails to do both faces double penalties.

Part III-Specific Penalty Triggers

Part III errors that can result in penalty assessments include:

  • Blank Part III when coverage was provided: Form is incomplete
  • Missing covered individuals: Form is incorrect
  • Wrong SSNs or names: Form is incorrect (may generate separate TIN notices)
  • Incorrect covered months: Form is incorrect
  • No continuation forms for large families: Some individuals not reported

The IRS does provide relief for "reasonable cause" if an employer demonstrates good faith efforts to comply. Keeping documentation of your compliance processes, data collection efforts, and reasonable error corrections can help establish good faith.

Frequently Asked Questions About 1095-C Part III Self-Insured Requirements

Do all self-insured employers need to complete Part III of 1095-C?

Self-insured Applicable Large Employers (those with 50 or more full-time equivalent employees) must complete 1095-C Part III when individuals are enrolled in their self-insured plan. If you are a self-insured employer with fewer than 50 FTEs, you are not an ALE and would file Form 1095-B instead of 1095-C to report your covered individuals. The 1095-C Part III self-insured requirement applies specifically to ALEs that self-fund their health coverage.

What information is required for each covered individual in Part III?

For each person enrolled in your self-insured plan, Part III requires their full legal name, Social Security Number (or date of birth if SSN is unavailable), and the specific months during which they were covered. You must check the appropriate monthly boxes or the "all 12 months" checkbox if they had coverage the entire year. The information should be accurate as of the date the individual was enrolled in coverage.

Can I use date of birth instead of Social Security Number in Part III?

Yes, the IRS allows you to report date of birth if a covered individual's SSN is unavailable. This commonly occurs with newborns who do not yet have assigned SSNs or dependents who are reluctant to provide their SSN. However, the IRS prefers SSN reporting, and using date of birth may trigger follow-up notices requesting the SSN. Make reasonable efforts to collect SSNs from all covered individuals during enrollment.

What if an employee has more than six covered individuals?

Part III has space for only six covered individuals. If an employee's coverage includes more than six people (the employee plus numerous dependents), you must use additional Form 1095-C forms as continuation sheets. On continuation forms, complete Part III only, leaving Parts I and II blank. Include the employee's name and SSN at the top for identification purposes.

Do I report COBRA participants in Part III?

Yes, individuals who continue coverage under COBRA must be reported in 1095-C Part III for the months they are enrolled and paying premiums. Even though the former employee is no longer actively employed and you report "no offer" in Part II for those months, they remain covered under your self-insured plan and must appear in Part III. Stop reporting covered months when COBRA coverage ends.

How do I handle dependents added mid-year, like a newborn?

Report the newly added dependent in Part III for the months they were covered. Apply the first-of-month rule: if coverage began mid-month, the first covered month is typically the following month (unless your plan provides retroactive coverage effective the 1st of the birth month). For newborns, use date of birth if an SSN has not yet been assigned.

What happens if I make an error on Part III after filing?

If you discover errors after submitting your ACA forms, you should file corrected Forms 1095-C. Create a new 1095-C with the "CORRECTED" checkbox marked, fix the Part III information (add missing individuals, correct SSNs, adjust covered months), and transmit through the AIR system. Also provide corrected copies to affected employees. Filing corrections promptly demonstrates good faith and may mitigate penalty exposure.

Do I complete Part III if the employee waives coverage?

If an employee declines coverage and no family members are enrolled under their coverage, Part III is left blank. There are no covered individuals to report. However, in the unusual case where an employee waives coverage for themselves but enrolls dependents under your plan, you would complete Part III listing only the enrolled dependents, not the employee.

Is Part III required for employees in states with their own health insurance mandates?

Federal Form 1095-C with Part III is required regardless of state location. However, employees in states with individual mandate laws (California, New Jersey, Rhode Island, District of Columbia, Massachusetts) also require state-level reporting. The Part III covered individuals data typically flows to these state filings as well.

What is the deadline for filing 1095-C with Part III?

For tax year 2025, Forms 1095-C must be furnished to employees by March 3, 2026, and e-filed with the IRS by March 31, 2026. These deadlines apply to the complete form including Part III. Missing deadlines triggers the penalty structure described above.

How can I simplify Part III reporting for my self-insured plan?

The complexity of 1095-C Part III self-insured reporting makes specialized ACA software essential. Look for solutions that support bulk data imports of covered individuals, validate SSNs and names against IRS requirements, track monthly enrollment status, and automatically generate continuation forms when needed. BoomTax handles all of these requirements with comprehensive Part III support.

Can I outsource Part III reporting to my TPA?

Yes, many self-insured employers outsource ACA reporting to their Third-Party Administrator. TPAs often have direct access to enrollment data and can efficiently handle Part III completion. However, the employer remains ultimately responsible for compliance. Verify your TPA's ACA reporting capabilities and review forms before filing.

How BoomTax Simplifies 1095-C Part III Self-Insured Compliance

Managing 1095-C Part III self-insured reporting with thousands of covered individuals requires powerful, purpose-built software. BoomTax provides a comprehensive ACA compliance solution designed specifically to handle the complexities of self-insured employer reporting:

  • Bulk covered individuals import: Upload spreadsheets containing all enrolled individuals, including employees, spouses, and dependents. BoomTax automatically populates Part III for each employee's 1095-C based on your enrollment data.
  • SSN validation: The platform validates Social Security Numbers against IRS formatting requirements and flags potential issues before filing. Catch TIN problems before they become IRS notices.
  • Month-by-month coverage tracking: BoomTax tracks which months each individual was covered, ensuring Part III checkboxes accurately reflect your enrollment records.
  • Automatic continuation forms: For employees with more than six covered individuals, BoomTax automatically generates properly formatted continuation sheets.
  • No TCC required: BoomTax transmits directly to the IRS AIR system as an authorized transmitter. You do not need to obtain your own Transmitter Control Code.
  • State filing integration: For employees in mandate states (CA, NJ, RI, DC, MA), BoomTax uses your Part III data to generate required state filings from the same platform.
  • Over 500 validation rules: Comprehensive IRS rule checking catches Part II and Part III errors before submission, dramatically reducing rejection rates.
  • Print and mail services: Deliver 1095-C copies (with complete Part III) to employees through BoomTax's secure, tracked mailing service.
  • Unlimited corrections: If Part III errors are discovered post-filing, correct them at no additional cost.

BoomTax's pay-per-form pricing means you only pay for forms filed, with no subscription fees or hidden charges. This makes it cost-effective whether you are filing hundreds or thousands of 1095-C forms with Part III.

Ready to simplify your self-insured ACA reporting? Get started with BoomTax today and experience stress-free 1095-C Part III self-insured compliance.

Conclusion: Mastering 1095-C Part III for Self-Insured Plans

The question "do I need to complete Part III of 1095-C for my self-insured plan" has a clear answer for most employers: yes, if you are an Applicable Large Employer with a self-insured health plan and individuals are enrolled in that plan. Understanding and correctly completing 1095-C Part III self-insured requirements is a critical compliance obligation that protects your organization from significant IRS penalties.

Key takeaways for 1095-C Part III compliance:

  • Self-insured ALEs must complete Part III: You serve as both employer and coverage provider, requiring full reporting in all three parts of Form 1095-C.
  • Report actual enrollment, not offers: Part III lists only individuals who were enrolled in coverage, not those who were offered but declined.
  • Collect dependent SSNs proactively: Gathering Social Security Numbers for spouses and children during enrollment prevents year-end scrambling.
  • Apply the first-of-month rule: Coverage months are determined by whether coverage existed on the first day of each month.
  • Include COBRA participants: Former employees continuing coverage under COBRA are reported in Part III for their covered months.
  • Use continuation forms for large families: If more than six individuals are covered, generate additional 1095-C forms.
  • File corrections promptly: If Part III errors are discovered, file corrected forms quickly to demonstrate good faith.
  • Leverage specialized software: The complexity of Part III reporting makes ACA compliance software essential for accuracy and efficiency.

By understanding the 1095-C Part III self-insured requirements outlined in this guide and using appropriate tools like BoomTax, self-insured employers can meet their ACA obligations confidently. The investment in proper compliance processes and software pays dividends in avoiding penalties, reducing administrative burden, and ensuring employees receive accurate documentation of their health coverage.

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