Calculating net income after taxes involves summing up all revenue and gains and subtracting all expenses and losses. A business deducts taxes paid annually to calculate net income after taxes, as reported by the Houston Chronicle.
Calculate the revenue and gains earned during the year. Revenue is the profit realized from a normal business course, while gains are money that comes from outside the company such as winning a lawsuit. Secondly, calculate losses and expenses, and then deduct losses and expenditures from revenue and profits. This gives the total income before tax. Deduct the total annual tax paid during the year from the net income before tax to get a net profit after tax, states the Houston Chronicle.