How Personal Loan Interest Is Calculated

When you take out a personal loan, the "price" you pay for borrowing that money is interest. While most borrowers focus on the monthly payment amount, understanding how personal loan interest is calculated can help you save money over the life of your loan.

Most personal loans, including personal loans through Upgrade, use a method called simple daily interest paired with an amortization schedule. Here is a look at how those two systems work together to determine your costs.

Simple Interest vs. Compound Interest

The first thing to know is that personal loans typically use simple interest, not compound interest.

• Simple Interest: Interest is only calculated on the principal (the amount you actually borrowed).
• Compound Interest: Interest is calculated on the principal plus any interest that has already accumulated. This is common with credit cards but not as common for personal loans.

Because personal loans use simple interest, you aren't paying "interest on interest," which can make the cost more predictable.

The Role of Amortization

While the interest is "simple," the way you pay it back follows an amortization schedule. “Amortization” means your loan payments are spread out over time so that the loan is paid off exactly at the end of the term.

Even though your monthly payment stays the same, the way that money is divided changes every month:

• Early in the loan: Your principal balance is at its highest, so a larger portion of your monthly payment goes toward interest.
• Later in the loan: As you pay down the principal, there is less "balance" for the lender to charge interest on. Consequently, a larger portion of your monthly payment goes toward the principal.

How Daily Simple Interest Works

Many modern lenders use daily simple interest. This means that interest accrues (builds up) every single day based on your current principal balance. 

For example, let’s say you have a 36-month, $3,000 loan with a 25% interest rate, that would mean the interest would begin at a little over $2.05 per day.

$3,000 x (25% interest/365 days) = $2.0547

So, after 31 days, your loan will accrue $63.69 in interest.

Why Payment Timing Matters

Because interest is calculated daily, the exact day you make your payment can affect your balance:

• Paying Early: If you pay a few days before your due date, less interest has had time to build up. More of your payment goes toward the principal, which reduces the amount of interest you’ll be charged the following month.
• Paying on the Due Date: Your payment is split exactly as outlined in your original amortization schedule.

How to Lower Your Interest Costs

Understanding the math behind your loan gives you the power to reduce your total costs. At Upgrade, there are no prepayment penalties, which allows you to use some interest-saving strategies. Before using any of the following strategies, check your loan terms to see if you would be charged any fees:

2. Make Extra Payments: Any extra money you pay goes directly toward the principal. A smaller principal means less interest is calculated every day moving forward.
4. Pay Bi-Weekly: By paying half of your monthly bill every two weeks, you end up making 13 full payments a year instead of 12, significantly reducing the principal faster.
6. Sign up for Autopay: Many lenders, including Upgrade’s lending partners, offer a discount for using automated payments, which can lower your APR from day one.

Summary: Interest Calculation Factors

Explore Your Options

Ready to see how interest rates and terms affect your monthly budget? With Upgrade, you can check your rate and see a clear breakdown of your potential loan terms without any impact on your credit score.

No Impact To Your Credit Score: Checking your rate for a personal loan through Upgrade will not impact your credit score, but if a personal loan is issued to you, that will result in a hard inquiry.