Where do I put the code in to find the answer?

[ppp3]

I am filing state of Wisconsin Schedule SB. Social security benefits are not taxable in WI, so I put them on line 4. Do I also put the medicare insurance premiums withheld on line 6?

[DMarkM1]

Yes, on line 6 of the WI Schedule SB, you would enter amounts deducted for Medicare on your Social Security statement.  Here is an excerpt from the form instructions.

LINE 6:

You may be able to subtract all or a portion of the cost of your medical care insurance. “Medical care insurance” means a medical care insurance policy that covers you, your spouse, and dependents and provides surgical, medical, hospital, major medical, or other health service coverage (including dental insurance). If you are receiving social security benefits, the amount paid for medical care insurance includes the amount deducted from your monthly benefit for Medicare insurance (for example, Parts B and D)