your ex's HSA has nothing to do with your right to claim qualifying dependents.
from IRS PUB 969 page 9
https://www.irs.gov/pub/irs-pdf/p969.pdf
Qualified medical expenses are those incurred by the
following persons.
1. Your spouse and you. You are no longer his spouse so any medical expense he paid out of his HSA to cover your medical expenses would not qualify
2. Not relevant since it is not your HSA
3. Any person he could have claimed as a dependent on his return except that:
a. The person filed a joint return;
b. The person had gross income of $4,700 (2023 -$5050 for 2024) or more; or
c. not relevant since not filing jointly
For this purpose, a child of parents that are divorced, separated, or living apart for the last 6
months of the calendar year is treated as the dependent of both parents whether or not the custodial parent releases the claim to the child’s exemption.
C) One child is 22 and files their own taxes, so would that child have to also amend their taxes in order to be "compliant" with the HSA rule? They are not a FT student.
if this child has more than $5,050 in gross income for 2024. they can not be claimed by you as a qualifying relative on your return. Because they are over 19 and not a full-time student you can not claim them as a qualifying child.
This answer has been verified for accuracy by an Intuit expert employee
