Interest income is the money earned from lending funds or investing in interest-bearing accounts, such as savings accounts or bonds. When individuals or businesses deposit money in a bank, they may receive interest as a reward for allowing the bank to use their funds. This income is typically calculated as a percentage of the principal amount deposited or invested. Interest income is an important component of personal and business finance. It can help individuals grow their savings over time and provide businesses with additional revenue. Common sources of interest income include savings accounts, certificates of deposit (CDs), and government bonds.