Deductions & credits

Re: marketplace 1095a child is no longer a dependent does taxpayer claim all or leave some off fo...

You would allocate the amounts on the 1095-A and divide this between your child and yourself. 

Yes, you can allocate it however you choose. You can try multiple scenarios to see how it can benefit all concerned.

Please see this answer from ShawnaD

• If your parents did NOT tell the Healthcare Marketplace (usually when they applied for health insurance) that you were not going to be their dependent, you will NOT receive a 1095-A of your own.
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  • You will need to get a copy of your parents' 1095-A and enter it on your tax return.  On the screen after entering the 1095-A, you will check the box indicating that the policy was shared by somebody that is not on your tax return.  It will then prompt you with further questions to determine how much of it is "allocated" to you (even if it is 0%). Your parents would follow this same procedure.
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  • If there was Advance credit received (column C of the 1095-A), your parents have the option to claim 100% of the 1095-A on their tax return, or to "allocate" part (or all) of it to you.  If you both agree, the allocation can be anywhere from 0% to 100%.  If you can not agree and Advance credit was received (column C on the 1095-A), then it is divided by the number of people on the insurance policy.  For example, if the insurance policy covers 4 people, each person is allocated 25%.