Loan Interest Basics

Loan interest is the cost of borrowing money. When you take out a loan, you repay the original amount plus interest, which compensates the lender for providing the funds. Understanding how interest works makes loan payments much easier to interpret.

What interest represents

Interest is usually expressed as a percentage of the loan amount. It can be simple or compound, and it can be calculated daily, monthly, or yearly depending on the loan structure.

The basic interest formula

A simple interest formula looks like this:

Interest = principal × rate × time

This formula shows how interest grows based on the loan amount, the interest rate, and the length of time the loan is held.

Why interest changes over time

Many loans use amortization, which means each payment includes both interest and principal. As the principal decreases, interest charges shrink because interest is calculated on the remaining balance.

A simple example

If someone borrows $1,000 at a yearly rate, interest accumulates based on that amount. As payments reduce the balance, interest becomes smaller over time.

Common misconceptions

Loan interest is simply the cost of borrowing. Once you understand how it’s calculated and how it changes over time, loan payments become much easier to follow.