Is there a cap on medical expenses I can deduct?

[kelliserencsa]

For example, I claimed a fraction in 2015 of what I claimed in 2014 for medical expenses (my husband had several expensive procedures in 2015), but it doesn't seem to have had much of an effect on our refund. Why?

[xmasbaby0 · Accepted solution]

The medical expense deduction has to meet a rather large threshold before it can affect your return. The amount of medical expenses that will count toward itemization for someone under 65 is the amount that is OVER 10% of your adjusted gross income; for someone 65 or older it would be the amount over 7.5% of your AGI.  

You should only enter the amount that you paid in 2015—do not include any amounts that were covered by insurance or that are still outstanding.  Of course, your medical expenses plus your other itemized deductions still have to exceed your standard deduction before you will see a difference in your tax due or refund.

[kelliserencsa]

Thanks, xmasbaby0, but our expenses were certainly over the 10% of our AGI, and way over what they were in 2014 (like 5x over), but the refund did not reflect this. I guess I was hoping for a little more "help" by way of a larger refund, and hence my title question about a cap.

[xmasbaby0]

No, there is no cap.  You need enough itemized deductions to exceed your standard deduction, as well as enough medical expenses to meet the medical threshold.  And of course, you cannot get a bigger refund than the amount of tax that was withheld from you in the first place. (Unless you get earned income credit, or one of the very few refundable credits)
Your itemized deductions have to be more than your standard deduction before you will see a change in your tax owed or tax refund.  The deductions you enter do not necessarily count “dollar for dollar;” many of them are subject to meeting thresholds  (for example: only the amount of your medical deductions that are over 10% of your AGI or over 7.5% if you are 65 or older are “counted”) or are calculated by a percentage of what you entered. The software program uses all the IRS rules that apply to the expenses you enter, and it tells you if you have enough to use your itemized deductions or if using the standard deduction is more advantageous for you. Here are the Standard Deductions for 2015
Your standard deduction lowers your taxable income.  It is not a refund 
2015 Standard Deductions
Single    $6300  (65 or older + $1550)
Married Filing Separately   $6300  (65 or older +  $1250)
Married Filing Jointly           $12,600  (65 or older + $1250@)
Head of Household $9250  (65 or older + $1550)