ACA and COBRA compliance for employers: A complete guide

ACA and COBRA compliance trips up experienced HR teams more often than most people realize. And, unfortunately, it can be expensive.

Failing to comply with the ACA can result in a $100 tax per day per eligible individual that you've failed to cover, while a missed COBRA election notice can trigger $110 per day per affected individual. And the rules are specific enough that being "mostly right" still means being out of compliance.

What makes ACA and COBRA particularly tricky is that they overlap in timing, but run on completely separate rule sets:

• ACA governs who you must offer coverage to and how you report it

• COBRA governs what happens to that coverage when someone leaves

• Both involve strict deadlines, and both punish late action more harshly than wrong action

Many HR teams understand the rules individually but lose time at the intersection of the two, especially during busy periods like open enrollment, terminations, and headcount fluctuations that shift ALE status.

This guide breaks ACA and COBRA compliance down into the specific workflows HR teams need to manage. You'll learn who's covered, what forms to file, how to track eligibility for variable-hour employees, key deadlines, and how to keep from falling behind on any of it.

ACA reporting in plain terms

The ACA's employer mandate requires applicable large employers to offer affordable health coverage to full-time employees and report that coverage to the IRS annually. An applicable large employer (ALE) is any business that employed an average of 50 or more full-time or full-time-equivalent employees during the prior calendar year. The obligation sounds straightforward, but the details are where errors happen.

Full-time versus full-time-equivalent

The ACA defines full-time as averaging 30 hours per week, or 130 hours per month. Every employee who meets that threshold counts as a full-time employee for ACA purposes, regardless of what your company policy calls full-time.

Full-time-equivalent (FTE) is a separate calculation that exists only for the ALE headcount test. To determine whether your company qualifies as an ALE, you combine all full-time employees with a fraction representing part-time hours. For example, 40 full-time employees plus 20 part-timers who each average 60 hours per month gives you 40 + (20 x 60/120) = 50 FTEs. At 50, you're an ALE.

The distinction matters because FTE is only used to determine ALE status. Once you're an ALE, your reporting and coverage obligations apply to actual full-time employees (30+ hours), not to the FTE calculation. Confusing the two leads to either over-reporting or under-reporting, both of which are compliance problems.

How to generate and file Forms 1094-C and 1095-C

ACA reporting centers on two forms that work together. Getting the data right on these forms is the core compliance task for ALEs.

What each form is

Form 1095-C is the per-employee statement. It reports whether the employee was offered coverage, what kind of coverage was offered, and whether the employee enrolled for each month of the year. Every full-time employee who was employed for any part of the year gets a 1095-C.

Form 1094-C is the transmittal that summarizes ALE-level totals. It accompanies the batch of 1095-Cs when you file with the IRS and includes information about the employer's total employee count, how many were offered coverage, and whether the employer qualifies for any transition relief.

The step sequence

Filing ACA forms follows a specific sequence. Missing a step or getting the order wrong creates problems that are harder to fix after the fact. Here's what you need to do:

1. Confirm ALE status for the reporting year by running the FTE calculation described above

2. Assemble per-employee, per-month data, including hours worked, coverage offered, coverage enrolled, and affordability safe harbor used

3. Generate 1095-C forms for every full-time employee who worked any part of the year

4. Furnish 1095-C statements to employees by the IRS deadline (typically March 2)

5. File the 1094-C transmittal and all 1095-Cs with the IRS by the filing deadline (typically March 31 for e-filing)

6. E-file if you're submitting 10 or more forms (which is nearly every ALE)

The data assembly step is where most errors originate. If employee hours, benefits enrollment, and coverage offer data live in separate systems, pulling accurate per-employee, per-month records requires manual reconciliation. A system that tracks hours, coverage offers, and enrollment in one place generates the forms directly from existing data.

ACA affordability safe harbors

Coverage is considered affordable under the ACA if the employee's required contribution for self-only coverage doesn't exceed a set percentage of their income. Because employers can't always know an employee's household income, the IRS provides three affordability safe harbors that ALEs can use to determine whether their plan meets the threshold:

• W-2 safe harbor: the employee's required contribution doesn't exceed the affordability percentage of their W-2 Box 1 wages for that calendar year

• Rate of pay safe harbor: the contribution doesn't exceed the affordability percentage of the employee's hourly rate multiplied by 130 hours, or their monthly salary

• Federal poverty line safe harbor: the contribution doesn't exceed the affordability percentage of the federal poverty line for a single individual

Each safe harbor has different tradeoffs for administrative ease and cost exposure. The federal poverty line safe harbor is the simplest to administer since it uses a single published figure, but it typically results in the lowest required employee contribution. Whichever safe harbor you use should be documented and applied consistently.

Tracking ACA eligibility with measurement and stability periods

For employees with predictable schedules, determining full-time status is straightforward. For variable-hour and seasonal employees, the ACA provides a framework of measurement and stability periods that locks in a coverage determination for a defined span.

The three periods for variable-hour staff

The look-back measurement period is when you track a variable-hour employee's actual hours over a defined span (typically 6 to 12 months). If they average 30 or more hours per week during this period, they're considered ACA full-time for the stability period that follows.

The administrative period is an optional buffer (up to 90 days) between the measurement and stability periods. It gives you time to notify employees of their eligibility status and process enrollments.

The stability period is when the coverage determination is locked in. If the employee was measured as full-time, you must offer them coverage for the entire stability period, even if their hours drop below 30 per week during that time. The stability period must be at least as long as the measurement period and no shorter than six months.

For multi-location employers with large hourly workforces, tracking measurement periods manually is one of the most error-prone ACA compliance tasks. Each variable-hour employee has their own measurement period timeline, and a single missed lookback can mean failing to offer coverage to someone who qualified. This is where system-level tracking pays for itself.

COBRA basics: who must offer it and when

COBRA (Consolidated Omnibus Budget Reconciliation Act) requires employers with 20 or more employees in the prior year to offer continuation of group health coverage to employees and dependents who lose coverage due to a qualifying event.

Qualifying events that trigger COBRA eligibility include:

• Voluntary or involuntary termination (for reasons other than gross misconduct)

• Reduction in hours that causes loss of coverage

• Employee's death (for dependents)

• Divorce or legal separation (for spouse/dependents)

• Loss of dependent child status under the plan

• Employee becoming entitled to Medicare

The duration of COBRA coverage depends on the qualifying event:

• Termination or reduction in hours: 18 months

• Disability (with SSA determination within 60 days): 29 months

• Divorce, death, or Medicare entitlement: 36 months

Understanding the 20-employee threshold

The 20-employee threshold is based on the number of employees on more than 50% of the business days in the prior calendar year. If you drop below 20, COBRA may still apply for the current year based on the prior year's count.

Federal and state COBRA laws

For employers with fewer than 20 employees, federal COBRA doesn't apply, but many states have their own mini-COBRA laws that extend similar protections. Mini-COBRA requirements vary by state, and the range is wide:

• California's Cal-COBRA applies to employers with as few as two employees and provides up to 36 months of continuation coverage

• Washington, D.C. requires just three months

• New York's mini-COBRA applies to employers of all sizes

As a result, if you operate in multiple states, different mini-COBRA rules may apply at different locations. Benefits administration software can become critical to help you manage the different regulations.

The COBRA administration workflow

COBRA administration runs on strict notice timelines, and missing a deadline can create both a compliance gap and financial exposure.

These are the key deadlines:

• The employer must notify the plan administrator within 30 days of a qualifying event, such as termination or reduction in hours

• The plan administrator then has 14 days to send the COBRA election notice to the qualified beneficiary

• The beneficiary gets 60 days from receiving the notice (or from the date coverage would be lost, whichever is later) to elect COBRA coverage

• Once elected, the beneficiary has 45 days to make their initial premium payment

• After that, premiums are due monthly, with a 30-day grace period

To keep all five milestones in view: the employer has 30 days to notify the plan administrator, the plan administrator has 14 days to send the election notice (44 days total from the qualifying event), the beneficiary has 60 days to elect coverage, 45 days after election to make the first premium payment, and then 30 days of grace period on each subsequent monthly payment. Missing the 44-day notice window is the most common COBRA violation and can result in penalties of $110 per day per affected individual.

For HR teams, the most common error is the handoff between the qualifying event and the notice. When a termination is processed in the HRIS but COBRA notification is a separate manual step, the 30-day employer notice window can pass before anyone acts on it. A system that automatically triggers COBRA notification from the termination event eliminates this gap.

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4 tips for staying ahead of ACA and COBRA deadlines

ACA and COBRA compliance often comes down to data and calendar management. Four practices keep HR teams ahead of deadlines instead of scrambling to catch up.

1. Build one compliance calendar confirmed against the source dates

Create a single calendar that captures every ACA and COBRA deadline for the year, including 1095-C furnishing, 1094-C filing, measurement period start and end dates, and standard COBRA notice windows. Always confirm each date against the IRS and DOL source documents directly, as deadlines can shift year to year.

2. Fix the data at the source, not at filing time

ACA errors often trace back to bad source data: hours that weren't tracked correctly, coverage offers that weren't recorded, enrollment statuses that are out of date. Address these problems as they happen throughout the year. This prevents the last-minute February scramble and ensures that you're staying compliant year-round.

3. Automate the notices and eligibility math you can

COBRA election notices, ACA eligibility lookbacks, and measurement period tracking are all rule-based workflows that follow the same logic every time. Automating them eliminates the common human errors like missed notices, incorrect eligibility determinations, and late filings.

Rippling's benefits administration automates all three: ACA measurement periods are tracked on each employee's record, COBRA notices fire automatically when a qualifying event is detected, and 1094-C/1095-C forms are generated and filed directly from your existing coverage data.

4. Reconcile ACA and COBRA around open enrollment

Open enrollment is a natural checkpoint to verify that your ACA eligibility data is accurate, your COBRA administration is current, and your benefits records match what's actually in effect. Use the annual enrollment cycle to catch and correct discrepancies before they become filing problems. Here's an open enrollment guide for employers that walks you through everything you need to know.

Where Rippling fits

Rippling connects benefits administration, payroll, and employee records in one platform, so the data ACA and COBRA compliance requires already lives in one place. That means:

• ACA eligibility tracked on the employee record. Hours, coverage offers, and enrollment status are all maintained in the same system, so 1095-C generation pulls from existing data rather than requiring manual assembly

• Form generation and filing from existing coverage data. Rippling generates 1094-C and 1095-C forms directly from your benefits and employment records, furnishes statements to employees, and files with the IRS

• Benefits and COBRA are administered together. When a qualifying event occurs (such as a termination or reduction in hours), COBRA notification triggers automatically. Election tracking, premium collection, and coverage continuation are managed in the same system as your active benefits

Streamline ACA and COBRA compliance with Rippling

ACA and COBRA compliance shouldn't require pulling data from three systems and reconciling it in a spreadsheet every filing cycle, because that's how compliance gaps happen. Rippling keeps hours, coverage, eligibility, and COBRA administration in one platform, so the data is always current and the notices go out on time.

Explore Rippling Benefits to see how it handles ACA and COBRA workflows, or request a demo to walk through your specific compliance setup.

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