interest rates explained true cost

An interest rate is the amount lenders charge for borrowing money. It’s typically expressed as a percentage of the principal on an annual basis. Interest impacts your loan, so it’s crucial to have interest rates explained if you don’t have a complete understanding of how it works. 

How Are Interest Rates Determined?

Rates are determined by a combination of factors, including:

  • Central bank policies
  • Economic conditions
  • Market demand for loans

The Federal Reserve Bank plays a key role in setting benchmark rates, which influence the rates for personal loans, mortgages, auto loans, and other forms of borrowing.

Credit Score Impact on an Interest Rate

Your credit score significantly impacts the interest rates you’re offered on loans and credit cards. 

When you borrow money, a higher FICO score can lead to lower rates, saving you money over time. While not always possible, negotiating for better rates can be successful, especially if you have a strong credit history or are a long-standing customer with a financial institution. According to CNN, only about 20% of Americans have a score higher than 780 points.1

On the other hand, borrowers with low credit scores often receive high interest rates because they are considered high-risk borrowers. A “poor” FICO score is anything below 579 points.2 Lenders use high interest rates on bad credit loans to decrease the risk of lending. The interest paid on payday loans and no credit check loans can make up for or reduce a lender’s losses if a borrower cannot repay.

Several other factors can affect your interest rate, including:

  • Your credit history
  • Your annual income
  • Your debt-to-income (DTI) ratio
  • Policies of a particular lender

How Interest Rates Are Applied to Loan Payments

Two main types of loans are addressed here: amortized loans and non-amortizing or interest-only loans. 

Amortized Loan Payments

How does an amortizing loan work? Amortized loans have scheduled periodic payments that are applied to both principal and interest. Although the payments are equal in amount, the amounts of principal and interest vary each month. Usually, the amount of interest owed decreases as the amount of principal paid increases from one month to the next.

Non-Amortizing Loan Payments

Non-amortizing or interest-only loans are different from amortizing loans in that you don’t make any payments on the principal until a lump sum is required. As a result, the principal doesn’t decrease over the life of your loan. This type of loan may apply in mortgages and home equity lines of credit (HELOCs).

How Different Types of Interest Rates Affect the Cost of Borrowing

The cost of your loan can vary based on the type of interest rate given by lenders. Therefore, find out what type of interest rate applies before taking a loan.

  • Simple Interest — Simple interest means interest paid or computed on the principal only of a loan. The monthly payment first goes toward the particular month’s interest, and the remaining amount goes toward reducing the principal. 
  • Compound Interest — Compound interest is when you earn interest on the money you’ve saved and the interest you earn. Interest may be compounded on a semi-annual, quarterly, monthly, or daily basis. Ideally, you should have a savings account that has compound interest. 
  • APR — APR (annual percentage rate) reflects your loan interest rate plus all other related loan fees. It’s a more effective way to compare the cost of different loans than simply considering the interest rate. 

Understanding Interest Rate Fluctuations 

An interest rate can fluctuate based on economic conditions, inflation, and bank policies. Central banks, like the Federal Reserve, use interest rate adjustments to control inflation and help stabilize the economy. 

In fluctuating interest rate environments, borrowers should consider locking in fixed rates to avoid future increases, while savers can benefit from higher rates on savings accounts. It’s crucial to adjust your budgeting and investment strategies in response to these finance changes, focusing on reducing high-interest debt and maximizing returns on savings during periods of rising rates.

Interest rates have fluctuated significantly over the years. Historically, rates have seen highs during periods of economic boom and lows during recessions. Currently, interest rates are influenced by global economic trends and monetary policies, with a recent trend towards lower rates to stimulate economic growth post-pandemic.

Interest Rates in the Housing Market

Interest rates play a critical role in the housing market, particularly for mortgage loans. Currently, mortgage rates are relatively low, presenting opportunities for buying or refinancing. Understanding how mortgage rates work and keeping an eye on market trends can help you secure a favorable rate on a real estate property. 

Credit Cards and Interest 

Credit card interest can significantly impact your debt. To manage and reduce this burden, consider transferring balances to lower-rate cards, negotiating with your card issuer for a reduced rate, or paying off high-interest cards first. Staying informed about your card’s annual percentage rate and shopping around for better rates can also help manage credit card debt effectively.

Strategies for Lowering Interest Rates on Loans

You may wonder, “Can you pay off a loan early to avoid interest?” It’s possible to reduce the amount of interest you pay, but first you need to ensure your creditor does not charge prepayment penalties. A prepayment penalty is a charge for early repayment. 

If your lender does not penalize early payments on loans, you can use these strategies to reduce loan fees.  

Extra PaymentsMaking additional payments beyond the minimum required. This can be done monthly, annually, or as a lump sum.Reduces the principal faster, leading to less interest accrued over the life of the loan.
Bi-weekly PaymentsInstead of monthly payments, pay half the monthly amount every two weeks. This results in 26 half-payments (or 13 full payments) per year.Accelerates repayment and reduces interest, as you’re effectively making an extra payment yearly.
RefinancingReplacing the existing loan with a new loan that has a lower interest rate or more favorable terms.Can significantly reduce monthly payments and total interest paid, especially if rates have dropped.
Loan ConsolidationCombining multiple loans into a single loan, ideally with a lower average interest rate.Simplifies repayments and can reduce overall interest costs.
Debt Avalanche MethodPrioritizing repayment of loans with the highest rates while making minimum payments on others. Reduces the amount of interest paid over time by eliminating high-interest debt first.
Balloon PaymentsMaking small payments in the initial years, followed by a large ‘balloon’ payment at the end of the loan term.Useful for borrowers expecting a significant increase in income; reduces initial payment burden.
Flexible Repayment PlansPlans that allow for changes in repayment amounts based on income or financial situation. Common with student loans.Provides flexibility for borrowers with fluctuating income, potentially reducing financial strain.
Round-Up PaymentsRounding up your payments to the nearest $50 or $100.Increases the amount going towards the principal, subtly accelerating loan payoff.
Debt Snowball MethodFocusing on paying off the smallest debts first while paying the minimum on larger debts, then moving to the next smallest debt.Provides motivation as smaller debts are cleared, though not always the most efficient in terms of interest savings.

FAQs About Interest 

How do rising rates affect my savings and borrowing?

When rates rise, borrowers may pay more in interest for loans and mortgages. However, savers can benefit as the annual percentage rate (APR) on savings accounts typically increases, offering better returns on deposits.

What is the role of the Federal Reserve Bank in setting interest rates?

The Federal Reserve Bank, as the central bank of the United States, sets the federal funds rate, which influences rates across the economy. This rate impacts everything from personal loans to mortgage rates and plays a crucial role in the growth of an economy and inflation control.

Should I choose a fixed or variable interest rate for my loan?

The choice between fixed and variable interest rates depends on your financial stability and risk tolerance. Fixed rates remain the same throughout the loan term, offering predictability. Variable rates can fluctuate with market changes, potentially leading to lower interest payments but also higher risks if rates rise.

How do changes in interest rates affect my savings account?

Savings accounts are directly impacted by changes in interest rates. When interest rates rise, the interest you earn on your savings account typically increases, offering you a higher return on your deposits.

What is the Annual Percentage Rate (APR), and why is it important?

The APR is the annual rate charged for borrowing or earned through an investment, including any fees or additional costs associated with the transaction. Understanding the APR helps you compare the true cost of loans and the real return on savings accounts.

How do interest rates contribute to economic growth?

Interest rates play a pivotal role in economic growth. Lower interest rates make it cheaper to borrow money, encouraging spending and investment. Conversely, higher rates can slow down economic activity but help control inflation.

How do interest rates affect my mortgage payments and credit card debt?

The interest rate on your mortgage determines the amount of your monthly interest payments. A lower rate means lower monthly payments and vice versa. Understanding how interest rates are set can help you choose the right time to secure a mortgage.

How do interest rates affect my credit card debt?

The interest rate on your credit card dictates how much extra you pay on top of your borrowed amount. Lowering interest on your credit card can significantly reduce the cost of your debt.

What should I do in a scenario of rising interest rates?

In times of rising interest rates, consider locking in fixed rates for loans and mortgages. For savings, look for accounts offering higher rates to maximize your returns. Staying informed and adapting your financial strategy is key.

CreditNinja: Understanding an Interest Rate 

Understanding how interest rates work before you borrow money is crucial. Luckily, numerous online resources and financial literacy programs offer easy-to-understand guides on these topics. 

CreditNinja offers informational articles on interest and other finance topics through the Dojo. You can learn more about finance charges on a loan, qualifying for installment loans, and more! You can also use our free financial calculators to calculate the cost of different loan options. 


  1. The 800+ club: Secrets of people with high credit scores │ CNN
  2. What is a bad credit score? │ The Sun
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