While residual income can be used to describe the amount of net income after all costs are paid down, it also refers to the amount of money you continue to generate after your initial work is done. There are countless ways to make money, but some are much more time-intensive than others. Active income, for example, refers to when you directly act or perform a service for money, including salaries, wages, tips, commissions, and income from a business you’re actively involved with.
Residual income is calculated as net income less a charge for the cost of capital. The charge is known as the equity charge and is calculated as the value of equity capital multiplied by the cost of equity or the required rate of return on equity. Given the opportunity cost of equity, a company can have positive net income but negative residual income.