It's wording like that that's confusing. Once your income goes into a higher bracket, you are only taxed at that higher bracket for the income _that falls withi

It's wording like that that's confusing. Once your income goes into a higher bracket, you are only taxed at that higher bracket for the income _that falls within that new bracket._ The income that _pushed_ you into that bracket is taxed the same way. (and AGI does affect deduction phase-outs so there's that complication...)