Summary
If you make K 13,000,000 a year living in Zambia, you will be taxed K 4,997,072. That means that your net pay will be K 8,002,928 per year, or K 666,911 per month. Your average tax rate is 38.4% and your marginal tax rate is 38.5%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of K 100 in your salary will be taxed K 38.50, hence, your net pay will only increase by K 61.50.
Bonus Example
A K 1,000 bonus will generate an extra K 615 of net incomes. A K 5,000 bonus will generate an extra K 3,075 of net incomes.