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My medical expenses seem to be capping out.  It looks like it has to do with overall deductions?  If I remove a child care expense, my refund continues to go up with each medical expense I enter.  However, when I put the child care expense back in, my medical expense refund reaches a certain amount and won't go higher.  I'm nowhere near the personal deduction limit of $14,389, so why is this happening?

Your medical expenses is a non-refundable tax credit. A non-refundable tax credit reduces the amount of tax you pay on your taxable income. You will not get money back from a non-refundable tax credit, but you can use it to offset how much you will pay.
For example; If you determine that you owe $1,000 in personal taxes, but you’re also eligible for $500 in non-refundable credits, you’ll only pay $500. However, if you don’t owe any taxes and you are eligible for $500 in non-refundable tax credits, you will not get a $500 refund.

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