I know that I did pay points on my mortgage, but I don't know how man, where to look?

[baisleyrick]

Also I am unsure if I have already used this deduction..

[Opus 17 · Accepted solution]

On a purchase, points are fully deductible in the year you close if you meet certain tests.  If not, you must spread the points out over the life of the loan (usually 15, 20 or 30 years).  You must always spread out points on a refinance.

If you paid points they would be listed on the HUD-1 closing document.  Sometimes called origination fees.  But not all origination fees are points.  Origination fees are considered points if they are a percentage of the loan amount (not a flat fee) and if they are not assigned to any specific services like document processing, attorney fee, or other specific costs.

If you closed in an earlier year (not 2016) then you can't deduct any points unless you are using the spread out method. You would have to look at your previous tax returns and documents.   Points and interest are reported on schedule A lines 10-12.  You would need to check your 1098 from your lender and match up the interest to the interest on the tax return to see if you deducted points fully when you closed or are spreading them out.