Fixed vs Adjustable Rate Mortgages (ARM) Explained

When shopping for a mortgage, you will quickly realize there are many different types of loans. The two most common categories are Fixed-Rate Mortgages and Adjustable-Rate Mortgages (ARMs).

Choosing between them is one of the most important decisions you will make. Your choice affects your monthly budget, your risk level, and how much you pay over time. Let’s break down how both work.

Fixed-Rate Mortgages: Predictability

A fixed-rate mortgage is exactly what it sounds like: the interest rate stays exactly the same for the entire life of the loan (usually 15 or 30 years).

Pros of Fixed-Rate:

Predictability: Your principal and interest payment will never change. You can budget with confidence.
Protection from Rising Rates: If inflation rises and market interest rates go up to 8% or 9%, your rate stays locked at your original, lower rate.
Simplicity: They are easy to understand and compare with different lenders.

Cons of Fixed-Rate:

Higher Starting Rates: Fixed rates are usually slightly higher than the introductory rates of an ARM.

Adjustable-Rate Mortgages (ARM): Lower Start, Higher Risk

An adjustable-rate mortgage starts with a lower interest rate for a specific period (usually 3, 5, or 7 years). After that initial period, the rate adjusts up or down based on market conditions, usually once a year.

You will often see ARMs written like 5/1 ARM. This means the rate is fixed for the first 5 years, and then adjusts every 1 year after that.

Pros of an ARM:

Lower Initial Payments: Because the introductory rate is lower, your monthly payments in the first few years will be cheaper than a fixed-rate loan.
Good for Short-Term Living: If you plan to sell the house or refinance before the fixed period ends, you get the benefit of the low rate without the risk.

Cons of an ARM:

Risk of Increase: Once the fixed period ends, your rate could jump significantly, making your monthly payment unaffordable.
Complexity: You have to read the fine print regarding "caps" (the maximum amount the rate can increase per year and over the life of the loan).

Important Note: Our mortgage calculator assumes a fixed-rate mortgage. If you use an ARM, the calculation is only accurate for the initial fixed period (e.g., the first 5 years). After that, the payment will change.

Which One Should You Choose?

There is no single "best" loan, only the best loan for your situation:

Choose a Fixed-Rate if: You plan to stay in the home for a long time (more than 7 years), you are on a tight budget, or you simply prefer peace of mind. Most first-time buyers choose fixed-rate.
Choose an ARM if: You are buying a starter home and plan to move in 3 to 5 years, or if you expect your income to rise significantly in the future and plan to refinance later.

Conclusion

For the vast majority of buyers, a 30-year fixed-rate mortgage is the safest and most reliable choice. However, if you are financially savvy and plan to move quickly, an ARM can save you money. Always ask your lender for a "Loan Estimate" for both options to see exactly what the costs and risks are.

Educational Purposes Only: This article is for informational purposes only. ARMs carry significant risks if rates rise. Always review the terms, caps, and adjustment schedule with your lender before choosing a loan.