Do I really need Medicare Part B?

Yes. Medicare Part B is non-negotiable if you want to keep TRICARE For Life.

The Defense Health Agency requires Medicare-eligible TRICARE beneficiaries to be enrolled in both Parts A and B. The day you drop Part B (or fail to enroll), TFL ends.

This trips up a lot of retirees because the Part B premium feels like a new bill they didn't have before. But here's the math:

• The standard Part B premium in 2026 is roughly $185/month (higher with IRMAA).
• In exchange, you keep TFL — which covers virtually all of your Medicare cost-shares.
• Without Part B, a single hospital stay could cost tens of thousands of dollars out-of-pocket.

If the Part B premium is a financial strain, look at a Medicare Advantage plan with a Part B giveback. Veteran-focused MA plans can return $50–$170+/month back to your Social Security check while preserving TFL as a wraparound.

What does not exempt you from needing Part B:

• Having TRICARE Prime or Select before 65 — irrelevant after Medicare eligibility.
• Having VA healthcare — VA is a separate system that doesn't coordinate with TFL.
• Still working — only true employer coverage (yours or your spouse's) qualifies for a Special Enrollment Period.