Deduction of an HSA contribution to an adult dependent's account

[mx4]

I have an adult child over 26 years-of age that lives at home, has no income, and my wife and I pay almost 100% of their living expenses.  When we retired late last year and moved from our family's high deductible health plan onto Medicare, we set up a COBRA account that allows our child to continue on our previous HDHP as an individual for 3 years.  We pay the COBRA premiums. The HDHP has notified us that our child is eligible for an HSA account.  My questions are: (1) are the COBRA premiums deductible on my tax return, and (2) are HSA contributions to my adult dependent's HSA deductible on my tax return? Thanks for any help.

[PattiF]

You are able to deduct the COBRA premiums as a medical expense for your qualifying relative dependent.

According to the IRS, to be eligible to have contributions made to your HSA, you cannot be another person's dependent. 

Eligible Individual

To be eligible to have contributions made to your HSA, you must be covered under a high deductible health plan (HDHP) and have no other health coverage except certain disregarded coverage. If you are an eligible individual, anyone can contribute to your HSA. However, you cannot be enrolled in Medicare or be another person's dependent. An individual does not fail to be treated as an eligible individual for any period merely because the individual receives hospital care or medical services under any law administered by the Secretary of Veterans Affairs for a service-connected disability. You must be, or be considered, an eligible individual on the first day of a month to take an HSA deduction for that month (see Last-month rule next).

[Mike9241]

your child, based on what you provided, is your dependent. a dependent can not make an HSA contribution. 

the maximum HSA contribution for family HDHP coverage is $7300 for 2022 (assuming neither you nor your spouse is over 55) there is no extra deduction for having a dependent.

the plan simply doesn't know that your son qualifies as your dependent. 

[Opus 17]

Based on your information, your child qualifies to be claimed by you as a dependent.  For that reason, they must answer "yes, I can be claimed by someone else as a dependent" even if they don't want to be claimed and even if you were willing to not claim them.  Since they can be claimed, they are ineligible to make HSA contributions, even if they are covered by qualifying HDHP insurance.

Even if the child was eligible to make HSA contributions, they would be reported on the child's tax return, not the parents.  An HSA is owned by an individual, and only the owner can deduct contributions, assuming the owner is eligible to make contributions.

Because you can claim your child as a dependent, you can claim insurance premiums you pay to cover your child as itemized deductions on your return.