They are marginal, but the margins depend on your entire income, not just capital gains income. So people with small amounts of capital gains income will tend

They are marginal, but the margins depend on your entire income, not just capital gains income. So people with small amounts of capital gains income will tend to just fall into one bracket, and it will not necessarily be the 0% bracket. Here's the worksheet: https://taxmap.irs.gov/taxmap/instr/i1040gi-015.htm#w24811v12 https://taxmap.irs.gov/taxmap/instr/i1040gi-015.htm#w24811v1... You'll see that there are breaks at 0% (Line 8/11), 15% (Line 15/20), and 20% (Line 23). Looking at the lead-up to line 23 is the clearest part. Line 21 adds the part taxed at 0% (Line 11) and 15% (Line 19). Line 22 then subtracts that from the total gains (Line 12). That final amount is then taxed at 20%.