Summary
If you make $3,996 a year living in the region of Iowa, USA, you will be taxed $312. That means that your net pay will be $3,684 per year, or $307 per month. Your average tax rate is 7.8% and your marginal tax rate is 8.3%. 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 $8.31, hence, your net pay will only increase by $91.69.
Bonus Example
A $1,000 bonus will generate an extra $917 of net incomes. A $5,000 bonus will generate an extra $4,585 of net incomes.