Qualified dividends, such as most of those paid on corporate stocks, are taxed at long term capital gains rates—which can be lower than ordinary income tax rates. In your case, they are being taxed at the 0% rate which is why there is no effect on your refund or amount due.
The tax law divides capital gains into two different classes determined by the calendar. Short-term gains come from the sale of property owned one year or less; long-term gains come from the sale of property held more than one year. Short-term gains are taxed at your maximum tax rate, as high as 37% in 2018. Most long-term gains are taxed at either 0%, 15%, or 20% for 2018.
Guide to Taxes on Dividends
Capital Gains and Losses
