Deductions & credits

If your spouse is covered by an HDHP, and has no other disqualifying coverage, she can contribute to an HSA.  She does not have to be the "owner" of the HDHP, she just has to be covered by it.

If you are past age 65, your Medicare enrollment will be retroactive by 6 months.  e.g. if you sign up for Medicare in August 2026, your enrollment will be retroactive to February 1, 2026.  Enrollment in Medicare makes you ineligible to contribute to an HSA.  It does not make your spouse ineligible to contribute, as long as she is covered by an HDHP without other coverage. 

There's no real point in using an IRA to fund an HSA because your contribution is still limited by the usual rules.  In other words, if you are only eligible for one month in 2026 (because medicare starts Feb 1), you could only fund your HSA to the tune of 1/12th of the 2026 limit, regardless of whether you fund it by direct contribution or rollover.  You can't roll over an entire $9000+ if you are not eligible for that much.  

Receiving SSA benefits does not make you ineligible to contribute, it's Medicare enrollment that does it.

No one "applies" for an HSA, you just open the account and make contributions.  There is no such thing as a family or self HSA. It's just a bank account.  You can only make contributions if you have an eligible HDHP, and the amount you contribute to the HSA depends on what kind of HDHP you are covered by. 

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I don't think you told us when you plan to enroll in Medicare, that's a key date.  Generally, you will pay a large financial penalty for late enrollment unless you are covered by a workplace plan that provides as good or better coverage.

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As to your wife,

She can contribute to an HSA starting January 1, 2026, assuming the following facts are true:

1. She is covered by an HDHP (either her own single policy, a family policy under her name, or a family policy under your name)
2. She has no "other" medical coverage.  That means no medical FSA from her employer OR YOUR employer.  Or, she or you can have a "post-deductible FSA" (a special kind of FSA that can't be used until you meet all your deductibles).  Or, she or you can have a "limited purpose FSA" (a different kind of special FSA that only covers items that are not covered by a typical HDHP, such as certain dental and vision care expenses).  

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As to yourself, you can contribute to an HSA if you are "covered" by an HDHP (your own single plan, your own family plan, or your spouse's family plan), and have no other disqualifying coverage.  Your contribution limits will be affected by your eventual Medicare enrollment, you need to include that date in your planning.  

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1.  Should I, at January, on my year 70 (2026), get an Individual FSA plan or no coverage at all.

No FSA.  If you want to contribute to an HSA, you need to be covered by an HDHP (single or family) with no other coverage. 

2.  If so, that would require my wife to sign up in August 2025, for a simple FSA to cover both of us until 2026.

No FSA.  Because of your wife's plan year being August--July, if she enrolls in an FSA in August of 2025, that will make both of you ineligible for HSA contributions until at least August 2026.

3.  Can my wife, in August 2026, apply for her own individual HSA, independent of any plan I may have

No one "applies" for an HSA.  She can contribute when and if she is covered by an HDHP and has no other coverage. 

4.  Can she then apply for family HSA to get our combined limits, provided that I have no coverage?  or provided that I'm not under FSA, nor Medicare (full SSA) by that August 2026.

No one "applies" for an HSA. She can contribute when and if she is covered by an HDHP and has no other coverage.  She can contribute up to the family maximum if she is covered by a family HDHP, either under her name or your name.  

5.  Assuming that my wife got an HSA in August 2026, when is the time to factor in my own Medicare retro-active  '6-mo looking back'  

Your contributions to a HSA will be limited based on when you enroll in Medicare.  That will not affect your wife's contribution limits, which are determined by what kind of coverage she has.  

6.  Since SSA will pay only a maximum of six months of retroactive benefits, would asking for such delay, receiving say in January 2027 (my year 71), help at all in this quest, be at all related to Under-Medicare-effective, or be even possible

You need to talk to a financial planner.  There are too many moving parts.  However, declaring your retirement benefit is not, by itself, a disqualifying factor.  What counts is enrollment in Medicare.  You will pay a substantial penalty if you delay Medicare enrollment without having comparable coverage in place.  Those penalties might outweigh any tax savings from the HSA. 

7.  If I am able to carry out the delay from step 6, is there any other timing that influences, preventing me from getting a family HSA in January 2027? 

An HSA is just a bank account. What matters is that you can't contribute unless you have qualifying HDHP medical coverage (from yourself or your spouse) and no other disqualifying coverage, such as Medicare.