Do I need Medicare Part B if I have TRICARE For Life?

Yes. If you are a military retiree, a retiree’s spouse or a survivor, you must have Medicare Part A and Part B to keep TRICARE, and TRICARE For Life only pays while Part B is in force. There is no TRICARE For Life enrollment and no TRICARE For Life fee. The premium you pay is Medicare’s, $202.90 a month in 2026 before any income surcharge, and in exchange TRICARE steps in behind Medicare and picks up most of what it leaves. Decline Part B, drop it, or miss the premium, and TRICARE stops with it. That is the whole rule, and it does not bend for people who are still working.

I write about Medicare for the north Valley, and TRICARE For Life is the exception to most of it. The Luke Air Force Base clinic sits on Litchfield Road in Glendale, and the households it produced over forty years of retirements are spread across the west side: Glendale’s older neighborhoods, the Peoria core along 83rd and Thunderbird, Westbrook Village, and a steady number who moved up to Vistancia and the 85383 corridor in the last few years. For those families the Part B question that everyone else weighs for months has one answer, and most of what gets marketed to a 65-year-old in this ZIP is something they already have. Here is what you need, what you do not, and the two places people get caught.

Why TRICARE For Life needs Part B at all

TRICARE For Life is not a plan you join. TRICARE describes it as Medicare-wraparound coverage that is automatic if you are TRICARE-eligible and have Part A and Part B, regardless of age or where you live. Medicare pays first for anything Medicare covers, TRICARE pays second, and for a service both programs cover you generally have no out-of-pocket cost. For the small set of things TRICARE covers and Medicare does not, TRICARE pays as though it were your only coverage, and you pay TRICARE’s normal cost share.

The mechanism only works if Medicare is paying first. That is why TRICARE ties eligibility to Part B, and why its guidance for retirees is blunt: you lose your TRICARE coverage if you do not have Part B, if you drop Part B, or if you fail to pay your Part B premiums. Part A is premium-free for almost everyone who served twenty years, so in practice the entire cost of keeping a lifetime of wraparound coverage is the Part B premium.

Source: TRICARE, "Retired service members and their family members" and the TRICARE-with-Medicare FAQs, tricare.mil. Rules are federal and apply identically in Maricopa County.

What Part B costs a military retiree in 2026

The standard Part B premium is $202.90 a month, and TRICARE does not pay any of it. That is the number most retirees have in mind. The number that surprises them is the surcharge.

Part B premiums are income-related. Medicare looks at your tax return from two years back, so your 2026 premium is set by your 2024 modified adjusted gross income, and the surcharge starts above $109,000 for a single filer and $218,000 for a couple filing jointly. A retired officer with a pension, a working spouse, a required minimum distribution and a rental in Westbrook Village crosses that line more often than people expect. At the first tier Part B runs $284.10 a month instead of $202.90, and it climbs from there. You can see where you land in about a minute.

Two things follow from that. First, the surcharge is not a reason to skip Part B. Without Part B there is no TRICARE For Life, and replacing what it does on the open market would cost far more than the surcharge. Second, the year you retire from a second career is usually the year to ask Social Security to reconsider, because a drop in income after a work stoppage is one of the events that lets them use a more recent year.

Still working at 65 with employer insurance? This is the first trap

Medicare’s own rule is well known: if you have group coverage through a current employer with 20 or more employees, you can delay Part B, and when that coverage ends you get an eight-month Special Enrollment Period to sign up with no penalty. Plenty of Luke retirees are in exactly that position at 65, in a second career with a defense contractor, the school district or a hospital system.

TRICARE does not honour the delay. Its FAQ for people who plan to keep working says, in so many words, that you will not have TRICARE coverage if you do not have Medicare Part B, and that your TRICARE For Life coverage starts the same day your Part B starts. So the real choice is not “delay Part B or not.” It is whether you want your employer plan alone until you retire, or your employer plan with Medicare and TRICARE behind it now. When you have all three, the order is employer plan first, Medicare second, TRICARE last, and TRICARE will usually want a paper claim with the other two explanations of benefits attached.

For many households the honest answer is to pay the premium and keep TRICARE in force, because a gap is where problems live: a spouse’s surgery that lands in the wrong month, a hospital stay that the employer plan covers with a large deductible TRICARE would have absorbed. I wrote up the general version of the working past 65 decision separately, but if TRICARE is in your picture, read that post with this paragraph in front of it.

Do I need a Medicare Supplement or a Medicare Advantage plan on top?

This is where a Luke household gets sold something, so let me be plain about both.

A Medicare Supplement, almost never. A Medigap policy exists to pay the deductibles and coinsurance that Original Medicare leaves behind. That is the job TRICARE For Life already does, with no network, in any state, with any provider who accepts Medicare. Paying a monthly Medigap premium on top is paying twice for the same gap. The only households where I would even open the conversation are ones expecting to lose TRICARE eligibility, which is rare.

A Medicare Advantage plan, usually not, but it is not forbidden. TRICARE’s answer is that you do not lose TRICARE For Life by enrolling in an Advantage plan. Medicare stays primary and TRICARE stays second payer. What changes is the plumbing. Original Medicare claims cross over to TRICARE automatically, so a Medicare-approved bill is settled without you touching it. Medicare Advantage claims do not cross over. The plan’s copay for a specialist visit or a hospital day is yours until you file it with the TRICARE For Life contractor, with the plan’s explanation of benefits attached, and the contractor pays what TRICARE would have. It works, but you become the clearinghouse.

You also take on a network. The whole point of Original Medicare plus TRICARE For Life is that the Peoria retiree who goes to Arrowhead for cardiology, Sun City for orthopedics and the Luke clinic for a refill never has to check whether any of them is in-plan. An Advantage plan draws a line around some of those, and in the fast-growing 85383 corridor practices change hands often enough that the line moves. What an Advantage plan offers in return is the extras Medicare and TRICARE do not: hearing aids, a gym benefit, over-the-counter allowances, sometimes a Part B premium reduction. If one of those genuinely matters to you, it is a conversation, and the arithmetic is checkable. For most TRICARE For Life households it is not close.

Do I need Part D?

No, for coverage. TRICARE For Life includes prescription coverage through the TRICARE Pharmacy Program, and that coverage is creditable, which means you can go without a Part D plan for years and enroll later with no late-enrollment penalty if you ever need to. Filling at the Luke pharmacy, which accepts electronic prescriptions from civilian doctors, usually carries no copay for covered drugs; home delivery and retail network pharmacies sit behind it with modest cost shares.

TRICARE’s own guidance adds two reasons a Part D plan is still worth comparing. A Part D formulary may cover a drug TRICARE’s does not, and TRICARE flags certain weight-loss medications as an example from mid-2026. And someone with limited income may qualify for Extra Help with Part D costs. Neither applies to most of the retirees I meet in Peoria or Glendale, but if a specific drug is the issue, price it under both before assuming. Note that a Part D plan bought alongside TRICARE carries its own income-related surcharge on top of the plan premium, which is one more reason not to buy one you do not need.

What TRICARE For Life does not cover, and what to do about it

Dental and routine vision. Neither Medicare nor TRICARE For Life pays for routine dental care, and TRICARE’s retiree dental program was folded into the Federal Employees Dental and Vision Insurance Program some years ago. Retirees and their families can enroll in FEDVIP dental, and in FEDVIP vision if they are in a TRICARE health plan, during the Federal Benefits Open Season, which this year runs November 9 through December 7, 2026 for coverage starting January 1, 2027. It is the same window as Medicare’s own open enrollment, and it is the one date on this page that a TRICARE For Life household actually has to act on. Anyone who would rather compare a private dental, vision and hearing policy against the FEDVIP options can do that with me; it is one of the lines I write alongside Medicare.

Long-term custodial care. Medicare does not pay for help with bathing, dressing and meals in an assisted living community or at home, and TRICARE For Life follows Medicare’s definition of skilled care, so it does not either. In Arizona the median assisted living community ran about $6,250 a month in the 2025 survey. I have written about what Medicare pays in assisted living and the ways households fund the rest, and for a retiree with a pension and a paid-off house in Trilogy the question is worth an hour with a licensed professional before it is urgent. That is education, not a product pitch; there is no rate I can quote you in an article.

Care outside the country. Medicare pays almost nothing overseas, but TRICARE For Life does cover care abroad as if it were your only insurance, with TRICARE’s cost shares. That matters for the Peoria snowbird with a place in Rocky Point more than most people realise, and I covered the Medicare side of it in Does Medicare cover me in Mexico?

What to do before your 65th birthday

If you are a retiree or a retiree’s spouse turning 65 in the next six months, the list is short and the order matters:

1. Enroll in Part A and Part B no later than two months before your birthday month. TRICARE’s own advice is two months, because a Part B effective date that slips a month is a month with no TRICARE. If you already draw Social Security, both parts arrive automatically; if not, check your dates and apply through Social Security yourself.
2. Check that your information in DEERS is current, especially your Medicare status once the card arrives. TRICARE For Life is automatic, but automatic means “from the records,” and a stale record is the second most common reason a claim bounces.
3. Do not buy a Medigap policy, and think twice before an Advantage plan. If a salesperson at a Peoria community centre tells you TRICARE For Life is “not enough,” ask them to name what it leaves uncovered. The honest list is dental, vision, custodial care and a few extras, and each has a less expensive answer than a second premium.
4. Put November 9 on the calendar if you want FEDVIP dental or vision for 2027.
5. Run your 2024 income through the IRMAA estimator so the first Part B bill is not a surprise, and if you retired from a second career this year, ask about an appeal.

And if your situation is one of the messy ones, a spouse still on an employer plan, a survivor benefit, a sponsor who retired from the Reserves, that is a phone call rather than a search. Call (602) 844-6002 and we will sort out which column of the table you are in. It costs nothing, and if the answer is “keep Part B, keep TRICARE, buy nothing,” that is what you will hear.