Summary
If you make $39,958 a year living in the region of Iowa, USA, you will be taxed $7,648. That means that your net pay will be $32,310 per year, or $2,692 per month. Your average tax rate is 19.1% and your marginal tax rate is 25.0%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of $100 in your salary will be taxed $25.04, hence, your net pay will only increase by $74.96.
Bonus Example
A $1,000 bonus will generate an extra $750 of net incomes. A $5,000 bonus will generate an extra $3,748 of net incomes.