If you make GH₵ 1,800,000 a year living in Ghana, you will be taxed GH₵ 593,007. That means that your net pay will be GH₵ 1,206,993 per year, or GH₵ 100,583 per month. Your average tax rate is 32.9% and your marginal tax rate is 33.9%. This marginal tax rate means that your immediate additional income will be taxed at this rate. For instance, an increase of GH₵ 100 in your salary will be taxed GH₵ 33.85, hence, your net pay will only increase by GH₵ 66.15.
A GH₵ 1,000 bonus will generate an extra GH₵ 662 of net incomes. A GH₵ 5,000 bonus will generate an extra GH₵ 3,308 of net incomes.