Get your taxes done using TurboTax

are you referring to "Accrued Market Discount" in Box 1f on your 1099-B, for example on a discounted Treasury Note or Muni?  This is taxable as ordinary income and will transfer to your Schedule B.  Even on a Muni if you purchase it at a discount greater than the "deminus" amount (0.25% per year til maturity) this AMD is taxable not tax-exempt.