The Post-Open Enrollment Audit Nobody Taught You (And Why Your January Depends On It)
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It’s the middle of June. An employee calls you — her voice is shaking. Medicare keeps denying her claims. Every single one. She can’t figure out why, and neither can her doctor’s office. You pull up her record. She terminated coverage six months ago. Back in December. The termination was processed. The box was checked. You closed open enrollment in January, feeling pretty good.
Except the file that fed out to your carrier after OE sent a null value in her term date field. And your carrier read that null as “still active.” So Medicare looked at her, saw active employer coverage on file, and denied every claim she’d submitted since January.
Now you’re on the phone with the carriers. For three months. Escalating up every chain you can find. Begging for a six-month retro-termination when the contract limit is 60 days. It all comes down to whether one human at the carrier will grant the exception.
That employee was mine. That phone call actually happened. And every bit of it could have been caught back in January — if anyone had told me to audit the feed.
Nobody does.
Here’s what they don’t tell you on day one of this job: the close of your open enrollment window is not the finish line. It’s the halfway point.
Most OE content treats enrollment like a race that ends when the portal closes. You send out the “congrats, OE is done!” email. You take a breath. You file it under complete. That feels right. That also happens to be the reason benefits administrators get blindsided every single January.
Because after OE closes, the real work starts — the work nobody put on your training plan. Files feed out to carriers. Carriers process those files their own way. Payroll pulls deductions from a separate system. And the handoffs between all three? That’s where things break. Quietly. For months. Until somebody calls you in a panic and you realize you’ve been running on luck.
The 5-phase audit I wish someone had handed me
After 20 years in benefits and way too many near-misses like the Medicare story, I run the same 5-phase audit every year. It’s the exact thing nobody taught me. Here’s what it covers.

Phase 1: The file feed audit
Every carrier reads data a little differently. Some carriers treat a null value as “terminated.” Others read it as “no change — keep them active.” Some require a specific term date and reject anything else. You don’t get to assume. You ask — in writing — and keep the answer on file.
Pull your full OE file. Count the terminations. Count the adds. Count the coverage tier changes. Compare it to what your benefits admin system says happened. If the numbers don’t match, stop and find out why. The EDI feed can run “successfully” — green status bar and everything — while silently dropping records. A green light means the file transferred. It does not mean every record processed.

Phase 2: The notices you already sent
Early in my career, I used to panic every fall trying to distribute every required notice as a standalone document. Separate emails. Separate mailings. Separate proof-of-delivery trails. I was drowning in admin work that didn’t actually need to happen — because most of those notices were already bundled into the OE guide I’d already handed out.
The Summary of Benefits and Coverage. The WHCRA notice. Patient Protection. HIPAA special enrollment rights. All of them sitting inside the guide every employee already received.
Read your OE guide cover to cover. Flag what’s already in there. Then handle separate distribution for the notices the guide can’t cover on its own — CHIP notices for employees in premium assistance states, COBRA Initial Notices for newly enrolled employees, and Medicare Part D Creditable Coverage if it’s not embedded compliantly in your OE guide (the prominence rules are strict). Keep proof of delivery on every single one. “I think I sent it” is never a defense in an audit.

Phase 3: What doesn’t roll (and who’s about to lose something)
The inbox flood nobody warns you about:
1. “Where did my FSA money go? I thought it rolled over.” (It didn’t. IRS requires annual re-election.)
2. “Why can’t I contribute to my HSA? I enrolled in the HDHP like you told me.” (Their FSA grace period is still running.)
3. “I thought my voluntary life was still active from last year.” (Not all voluntary benefits auto-renew.)
4. “My dependent got kicked off — nobody told me I had to re-verify.” (Expired documentation nobody flagged.)
This is a two-part audit. First, flag every election type and mark whether it auto-renews or requires active re-election. Then — and this is the part most admins skip — build a targeted list of the people about to lose something. Not a mass email. A specific message to Sarah, who’s about to zero out her FSA, and to Marcus, whose spousal surcharge attestation just expired.
And then there’s the PPO-plus-HCFSA-to-HDHP trap — the one that catches everybody. An employee switches from your PPO to your HDHP during OE. Thinks they can start contributing to an HSA on January 1. They can’t. Because their Healthcare FSA has a March 15 grace period, they’re technically still covered by a disqualifying health plan until that grace period closes — usually April 1. Any HSA contribution before then is an excess contribution with IRS penalties attached. Tell them before OE closes. Not after.

Phase 4: Pre-payroll reconciliation (before the first paycheck, not after)
The first week of January is the worst week of the year for a benefits admin — not because of the work, but because of the inbox. Forty variations of “my deduction is wrong.” All preventable. All caused by the handoff between your benefits admin system and your payroll system going sideways, and nobody catching it in time.
Pull a sample of 20 employees — different coverage tiers, different benefits, mix of pre-tax and post-tax. Compare their elections against the payroll preview. Line by line. Before payroll runs. Flag every discrepancy, even small ones. A $2 difference is a rounding error. A $20 difference is a coverage tier mismatch. A $200 difference is a plan-level mapping error affecting multiple people.
Do not — I repeat, do not — wait until the first January paycheck to find out deductions are wrong. By then, FSA funding is off, tax calculations are wrong, and you’re doing retro corrections in the busiest inbox week of the year. Verify at the preview stage. Every year.
Phase 5: The year-round rechecks that save careers
The Medicare story from the beginning? It got caught in June. Six months too late. Because nothing on my calendar told me to look. Put these on your calendar now — recurring, with reminders:
- January, post-first-feed: reconcile what fed to carriers against what should be in effect
- January, first paycheck: spot-check 3–5 employees across coverage tiers
- February: second-month carrier file check — silent January errors surface here
- April: HSA eligibility check for anyone who migrated from PPO-plus-HCFSA to HDHP
- June: the non-negotiable mid-year audit — cross-reference your ben admin system, your carrier files, and your payroll deductions
- September: pre-OE data hygiene pass
- October 15: Medicare Part D Creditable Coverage Notice distributed
Luck is not a strategy. Calendar reminders are.
The free field guide I built so you don’t have to
I wrapped all five phases into a free PDF field guide called The Post-OE Audit. Every phase walks you through what to check, what to watch for, and how to know when you’re done. There’s a companion Excel tracker built to match — dropdowns, seeded lists of common notices, auto-calculated variance between your ben admin system and your payroll preview.
It’s free. It lives at ericakirby.com. Go grab it before next January sneaks up on you.
And if you want the system that runs OE from kickoff to close — not just the post-OE side — the Open Enrollment Mastery Kit is the full 34-page playbook with a 9-tab Excel calculator and the OE Timeline Checklist I wish someone had handed me on day one.
1. OE doesn’t end when the portal closes — the file feed does.
2. Every carrier reads null values differently. Ask. Get it in writing.
3. Most required notices are already in your OE guide — stop distributing them twice.
4. FSAs don’t roll over. Tell your people before they lose the money.
5. The first January paycheck is the wrong place to find a deduction error. Check the preview.
Nobody should have to figure this out alone. Especially not with someone’s Medicare coverage on the line.
— Erica

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