Rainman12 is correct - if your HSA contributions are all listed on your W-2 in box 12 with a code of W, then this is an "exclusion", that is, the HSA contribution amount is removed from your income. There is no "deduction" because it was never in your income in the first place.
To explain a bit further: if you have an amount with code W in box 12 of your W-2, then this amount is removed from Wages in boxes 1, 3, and 5 before your W-2 is printed.
This is how most taxpayers contribute to an HSA.
If, on the other hand, you made direct contributions to your HSA (i.e., not through your employer), then the deduction will appear on line 25 of Schedule 1 (Form 1040).
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