Passive income differs from earned income and portfolio income in a variety of ways. Passive income is generally defined as a stream of income earned with little effort, and it is referred to as progressive passive income when there is little effort needed from the individual receiving the passive income in order to grow the stream of income. Examples of passive income include rental income and any business activities in which the earner does not materially participate during the year.
When money is lent to a partnership or S-corporation acting as a pass-through entity (essentially a business that is designed to reduce the effects of double taxation) by that entity’s owner, the interest income on that loan to the portfolio income can qualify as passive income. According to the IRS's Passive Activity and At-Risk Rules: "Certain self-charged interest income or deductions may be treated as passive activity gross income or passive activity deductions if the loan proceeds are used in a passive activity."