FEHB Plan Comparison for Medicare Retirees: BCBS, GEHA, and Aetna Side by Side

Why Your FEHB Plan Choice Changes After Medicare

When Medicare becomes your primary payer, the cost-sharing math for your FEHB plan shifts dramatically. Benefits you relied on as an active employee — the plan's deductible waiver, its specialist copay structure, its out-of-pocket maximum — matter less when Medicare is paying first and your FEHB plan is only picking up what's left.

This creates an opportunity: retirees enrolled in expensive "High Option" FEHB plans often overpay for secondary coverage that does the same work as a cheaper plan. When Medicare covers 80% of outpatient costs and most FEHB plans waive their own cost-sharing on top of that, the difference between a $500/month High Option plan and a $200/month Basic plan can be negligible in actual out-of-pocket spending.

The best time to evaluate this is during Open Season (mid-November through mid-December), when retirees can switch FEHB plans through OPM's Services Online portal.

How Major Plans Handle Medicare Coordination

Every FEHB plan brochure has a section titled something like "Benefits When You Are Enrolled in Medicare." This section describes exactly how the plan's cost-sharing changes when Medicare is primary. Here's how the most popular national plans handle it:

BCBS Basic (Blue Cross Blue Shield)

BCBS Basic is already one of the lowest-premium national FEHB plans. When Medicare is primary:

• Plan deductible: waived
• Office visit copays: waived
• Coinsurance: waived for Medicare-covered services
• The plan includes an annual HRA (Health Reimbursement Arrangement) pass-through of approximately $800, which can offset a portion of Part B premium costs

For retirees on a High Option BCBS plan, switching to Basic after enrolling in Medicare Part B saves the premium difference while providing functionally identical coverage. The wrap-around benefit is the same — $0 at the point of care for Medicare-covered services.

GEHA Standard

GEHA Standard is another popular low-cost option. With Medicare primary:

• Plan deductible: waived for Medicare-covered services
• Copays: waived
• Coinsurance: waived

GEHA Standard doesn't offer the same HRA pass-through as BCBS Basic, but its lower base premium makes it competitive for retirees whose primary concern is minimizing monthly outflow. The net cost of FEHB premiums plus Part B premiums tends to be lower with GEHA Standard than with most High Option plans.

Aetna Direct (CDHP)

Aetna Direct is a consumer-driven health plan with a built-in HRA. When Medicare is primary:

• Plan deductible: effectively waived (Medicare satisfies it)
• The plan provides an annual HRA pass-through of approximately $900
• Out-of-pocket costs for Medicare-covered services: near zero

The HRA makes Aetna Direct appealing for retirees who want partial premium reimbursement. The $900 annual HRA offsets roughly 37% of the standard Part B premium ($2,434.80/year in 2026).

The High Option Downgrade Decision

If you're enrolled in a High Option plan — BCBS Standard, GEHA High, or a regional plan's top tier — the Open Season after your Medicare enrollment is the time to evaluate a downgrade.

The math is simple: compare what you're actually paying out of pocket under your current plan with Medicare primary versus what you'd pay under a Basic or Standard tier. For most retirees with Medicare Part B, the answer is the same: $0 out of pocket under both tiers for Medicare-covered services. The only difference is the monthly premium.

What a downgrade doesn't affect:

• Your Medicare coordination. Every FEHB plan coordinates the same way — Medicare pays first, FEHB pays the rest.
• Your access to Medicare providers. Provider networks are a Medicare function, not an FEHB function, when Medicare is primary.
• Your annual out-of-pocket cap. With Medicare covering 80% and FEHB covering the remaining 20%, you're unlikely to approach any FEHB plan's out-of-pocket maximum.

What a downgrade might affect:

• Prescription drug formulary. Different plan tiers sometimes have different formularies. Check whether your current medications are covered at the same tier in the Basic plan.
• Non-Medicare-covered services. Dental, vision, and hearing benefits (where offered) are plan-specific and not affected by Medicare coordination. If your High Option plan includes dental coverage that the Basic plan doesn't, factor that in.
• International coverage. Some High Option plans provide broader international emergency coverage than Basic plans. If you travel outside the US regularly, compare the international benefits sections.

FEHB Premium Reimbursement and HRA Features

Several FEHB plans offer HRA or premium reimbursement features specifically designed for Medicare-eligible retirees. These features effectively reduce the net cost of carrying both FEHB and Medicare Part B.

The reimbursement varies by plan and changes annually, so check the current plan year brochure. As a general framework:

• Plans with HRA features deposit funds annually into a reimbursement account
• These funds can be used for qualified medical expenses including Part B premiums (varies by plan)
• Unused HRA balances may roll over year to year (plan-specific)

When comparing plans during Open Season, add the HRA value to your analysis. A plan with a $200/month premium and a $900 HRA may cost less net than a plan with a $150/month premium and no HRA: ($2,400 - $900) = $1,500 net vs. $1,800 for the cheaper plan without an HRA.

Self Only vs Self Plus One After Medicare

When both spouses are Medicare-eligible, some couples switch from Self and Family (or Self Plus One) to two separate Self Only enrollments — potentially in different FEHB plans optimized for each person's needs.

Whether this saves money depends on the specific plans. Two Self Only premiums can be more or less than one Self Plus One premium depending on the carrier. Run both scenarios during Open Season with the OPM comparison tool.

One constraint: if a surviving spouse needs to continue FEHB coverage after the retiree's death, the retiree must be enrolled in Self Plus One or Self and Family at the time of death (plus a survivor annuity must be in effect). Two separate Self Only plans don't protect the surviving spouse's FEHB eligibility.

The FEHB & Medicare Coordination Guide includes a plan comparison framework and the exact steps for switching plans during Open Season as a retiree.

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