Open enrollment prep is loud. The Medicare Part D creditable coverage disclosure is quiet — until someone asks why a retiree got a late-enrollment penalty letter.
If your group health plan includes outpatient prescription drug coverage (most do), you generally must tell Medicare Part D eligible individuals each year whether that coverage is creditable — actuarially expected to pay, on average, at least as much as Medicare’s standard Part D benefit. CMS publishes model notices and a creditable-coverage overview employers and TPAs lean on.
The two deadlines (calendar-year plans)
For plan years that track the calendar year, the annual rhythm is:
| Who | What | When | | --- | --- | --- | | Medicare Part D eligible individuals | Written disclosure (creditable or non-creditable) | Before October 15 each year | | CMS | Online disclosure of whether coverage is creditable | By October 14 each year |
The individual notice and the CMS filing should describe the same creditable / non-creditable conclusion for the upcoming plan year. CMS also expects disclosures when someone becomes eligible mid-year, when coverage ends, and in other change-in-status situations described in its guidance — not only the annual mailing.
Non-calendar-year plans follow the same concepts on their own plan-year calendar; map dates off your SPD, not January 1 by reflex.
What “creditable” actually means
Creditable coverage is an actuarial test, not a vibes check from the PBM invoice. Someone qualified to opine — often the plan’s actuary or prescription-benefit consultant — compares expected drug spend under your group plan to the standard Part D benefit and documents the result.
If coverage is not creditable, Medicare-eligible individuals who delay Part D enrollment without other creditable coverage can face a permanent late-enrollment penalty when they eventually enroll. That is why the notice language matters even for employers who do not “do Medicare.”
Why late August
October feels far away until September vendor queues fill up. In practice, August is when you should:
- Confirm whether 2026 (or the applicable plan year) coverage is creditable or not — and get that in writing from the actuary or carrier.
- Decide how the notice goes out (standalone mailing, OE packet insert, secure email where allowed, etc.).
- Schedule the CMS online disclosure so it is not a single person’s October 13 panic.
- Brief call-center and HR generalists on where to send Medicare questions (hint: not “check your FSA balance”).
What employers should do
- Ask your TPA, carrier, or actuary for the creditable / non-creditable determination for the plan year you are about to disclose.
- Use the CMS model notices (or counsel-approved equivalent) — do not freestyle the penalty language.
- Mail or deliver individual notices before October 15; log proof of mailing or electronic delivery.
- Complete the CMS online disclosure by October 14 for calendar-year plans.
- Add new hire / loss of coverage triggers to your admin checklist so mid-year events do not rely on the annual batch alone.
CBA administers medical FSAs, HSAs, HRAs, COBRA, and consolidated billing — we see the October compliance pileup every year. This notice belongs on the same calendar as ICHRA employee notices and OE kits, not in a forgotten Medicare folder.