Unfortunately, you cannot deduct your 2015 deductions on your 2016 tax return. You will need to amend your 2015 tax return to include
it.
Amending is done on Form 1040X. Amended returns have
to be printed and filed by mail. It can take the IRS up to 12 weeks or
longer to process them. If you are due a larger refund than on your
original return, your amended return should only show the difference and you
will receive a separate check for it. If you owe money on your amended
return, it will show only the new amount owed, you will have to mail a check
with the return.
How to Amend?
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