Glossary
Special Enrollment Period (SEP)
An enrollment window triggered by qualifying life events — TRICARE and VA care do NOT trigger one.
Also known as: SEP, Medicare Special Enrollment, Working Aged SEP
Quick answer
A Special Enrollment Period allows you to enroll in Medicare Part B outside your IEP without a late-enrollment penalty. The most common SEP is the 'Working Aged' SEP: you (or your spouse) are actively working and covered by an employer group health plan with 20+ employees. After the employment or coverage ends, you have 8 months to enroll in Part B penalty-free.
Why it matters
SEPs save you from permanent late penalties — but only if your delay was based on active employer coverage. Retired-military beneficiaries are routinely told (incorrectly) that TRICARE 'counts' as employer coverage. It does not. The wrong assumption here is the single most expensive Medicare mistake retirees make.
Why this matters at age 65
If you (or your spouse) are still working past 65 with employer coverage from a 20+ employee company, you can safely delay Part B and keep TRICARE Prime/Select. Once that employment ends, you have 8 months to enroll in Part B without penalty AND that's the trigger for your TFL transition. Outside this narrow scenario, NO TRICARE or VA situation grants an SEP.
When you'll encounter it
When you (or your covering spouse) retire or lose active employer health coverage after age 65.
Impact on Medicare
Lets you enroll in Part B without the late-enrollment penalty. Coverage begins the month after you enroll (or you can request retroactive coverage of up to 6 months).
Impact on TRICARE For Life
An SEP is the ONLY legitimate way to keep TRICARE Prime/Select past age 65 and transition to TFL later without penalty. The moment employer coverage ends, file for Part B within the 8-month window — and TFL activates with it.
Common misconceptions
- "TRICARE counts as employer coverage for SEP purposes." — It does not. CMS does not recognize TRICARE (Prime, Select, or any TRICARE program) as employer group coverage. Delaying Part B because of TRICARE = permanent late penalty AND loss of TFL.
- "VA healthcare gives me an SEP." — It does not. VA care is never creditable employer coverage for Medicare enrollment purposes.
- "FEHB (federal employee health benefits) counts as employer coverage." — Only if you (or your spouse) are still ACTIVELY employed by the federal government. FEHB held by a federal retiree does NOT trigger an SEP.
- "COBRA gives me an SEP." — COBRA does NOT extend the SEP. The 8-month clock starts when active employment ends, not when COBRA ends.
Common mistakes to avoid
- Believing the TRICARE briefing that said 'just keep TRICARE past 65' — terminates TFL and triggers lifetime penalty.
- Relying on COBRA past 65 — coverage gap and late penalty follow when COBRA expires.
- Forgetting the spouse's SEP is based on the WORKING spouse's employment, not the Medicare beneficiary's.
- Filing SEP paperwork (CMS-40B + CMS-L564 from the employer) more than 8 months after employment ends.
Real-world scenario: A retired Coast Guard captain works a second civilian career until age 68 with employer coverage at a 500-employee firm.
He delays Part B with no penalty. When he retires at 68, he files CMS-40B (Part B application) and CMS-L564 (employer coverage proof) within the 8-month SEP. Part B becomes effective the first of the next month, TRICARE Select terminates, and TFL activates — no gap, no penalty.
What should I do?
- 1If you (or your spouse) are still actively working with employer coverage past 65, request a Notice of Creditable Coverage from the HR department and keep it filed.
- 2Do NOT rely on TRICARE, VA, FEHB-retiree, or COBRA as a basis for an SEP — none of them qualify.
- 3When active employment ends, file CMS-40B (Part B enrollment) and CMS-L564 (employer coverage proof) with Social Security within 8 months.
- 4After Part B becomes effective, verify in milConnect that DEERS reflects both A and B dates so TFL activates cleanly.
Questions people commonly ask
- Can I delay Part B if I'm still working?
- Does TRICARE count as creditable employer coverage?
- Does FEHB count for SEP purposes?
- What forms do I need to file for an SEP?
Continue learning
— suggested by the knowledge graph- What is Medicare? A complete overview for retired militaryA plain-English, handbook-grounded overview of the federal health insurance program for people 65 and older, written specifically for retired service members and their families.
- Understanding Original Medicare (Parts A & B) for veteransExactly what Part A and Part B cover, what they cost in 2026, and why both are required to keep TRICARE For Life.
- Enrolling in Medicare: timing, methods, and the military-specific rulesWhen and how to sign up for Medicare Parts A and B — and the timing that protects your TRICARE For Life activation.
- Creditable Drug CoveragePrescription drug coverage that CMS certifies is at least as good as standard Medicare Part D — including TRICARE Pharmacy and VA Pharmacy.
- Disability Medicare Eligibility (Under 65)Medicare eligibility before age 65 — automatic after 24 months of SSDI, immediately for ALS, and based on dialysis/transplant for ESRD.
- IRMAA (Income-Related Monthly Adjustment Amount)An income-based surcharge added to your Medicare Part B and Part D premiums when your modified adjusted gross income exceeds CMS thresholds.
- Medicare EligibilityU.S. citizens and lawful permanent residents (5+ years) qualify for Medicare at age 65, or earlier with qualifying disability or ESRD/ALS.
- I'm still working past 65. Can I delay Part B?Only if you have true employer group health coverage from active employment (yours or your spouse's, 20+ employees). In that case you get a Special Enrollment Period later. But TFL won't activate until you take Part B.
- What is the General Enrollment Period?January 1 – March 31 each year. It's the backup enrollment window for people who missed their IEP and don't qualify for a Special Enrollment Period.
- Do I get a new TRICARE For Life card?No. There's no separate TFL card. Your uniformed services ID card and your red-white-and-blue Medicare card are your proof of coverage.
- I'm turning 65. What should I do first?About 3 months before your 65th birthday, sign up for Medicare Parts A and B at SSA.gov. TRICARE For Life activates automatically once both are effective and DEERS is current.
- Do I need Medicare Part A if I have TRICARE?Yes. TFL requires Part A and Part B. Part A is typically premium-free if you or your spouse worked 40+ quarters paying Medicare taxes.
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Related Official Resources
Continue learning straight from the source. Every link below goes to an official government or DoD resource.
Last reviewed January 2026 against the 2026 Medicare & You and TRICARE For Life handbooks.