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Interest rates are trending upward. They’ve only been going down since 2009 and now the pendulum is starting to swing the other way. When rates start to go up, an adjustable rate mortgage (ARM) starts to make a lot of sense.

However, while most consumers responsibly carry an ARM, there have been situations where the ARM didn’t make financial sense, and as a result, the loan earned a tarnished reputation. ARMs no longer involve the interest-only loans and optional payment plans that have distracted from the true nature of the loan option.

ARMs are 30-year mortgages where the rate remains fixed for a period of time – typically five, seven or 10 years. At the end of the fixed-rate period, the rate adjusts once per year up or down based on where rates currently are. You get a lower rate with an adjustable mortgage than you would on a comparable fixed loan because you’re not paying for 15 or 30 years of rate security.

The truth is, many consumers have benefitted from ARMs and prefer to use them as a tool to save money in the short-term while planning for the long-term. As rates rise, the spread between fixed and adjustable rates widens. For this reason, it can make a lot of sense to take an ARM as rates go up. Here’s information about ARMs, how to interpret the lingo and how to decide if it’s right for you.

Adjustable Rates 101

To comprehend the functionality of ARMs, there are a few terms to understand when talking to your mortgage banker to determine if this loan program is a good match for your financial situation:

Index: The economic indicator used to calculate interest rate adjustments for ARMs. The index rate can increase or decrease at any time.

Initial cap: This cap is the maximum amount the interest rate can adjust after the fixed-period. The initial cap and the periodic cap may be the same or different (i.e. 2/2/5 or 5/2/5).

Periodic cap: This cap puts a limit on the interest rate increase from one adjustment period to the next.

Lifetime cap: This cap puts a limit on the interest rate increase over the life of the loan. All adjustable-rate mortgages have an overall cap.

It would also help to be familiar with these terms in their numerical form, as this is the way in which your lender will illustrate the type of ARM you qualify for.

5/1: The five represents the amount of years the interest rate is fixed. The one indicates that the interest rate will adjust yearly after the fixed period.

2/2/5: (Note: Caps can be different depending on the term of the loan. For example, you may find that a 7-year ARM has a 5/2/5 cap structure). But for this example, the first two means that the most a rate can change is 2% the year after the fixed period expires. The second two means that the rate can change 2% every year thereafter, and the five means the maximum percentage that can be added to the initial rate for the lifetime of the loan.

For example, the maximum rate and payment you would experience for a $200,000 5/1 loan (2/2/5) at 3.99% would be:

Years Loan Amount Rate Principal & Interest  Payment
1-5 (initial loan) $200,000 3.99% $953 per month
6 (resets 2% higher) $177,136 5.99% $1,140 per month
7 (resets 2% higher) $173,978 7.99% $1,359 per month
8 (rate increase 1% more because 5% is the lifetime cap) $171,474 8.99% $1,472 per month


It’s important to note that while interest rates can rise, they can also decrease, making your payments smaller. The example above reflects the most you would pay if rates increased to the maximum or lifetime cap. Knowing the maximum amount you could end up paying on your ARM is important, because it will help you decide if it’s best to refinance prior to the expiration of the fixed rate, or continue to allow the rate to adjust because it is still cost-effective. It’s also worth mentioning that for the fixed period of the loan, the ARM gives you the opportunity to save thousands of dollars (money you would have spent on the fixed-rate loan). This could give you the opportunity to do a number of things.

You have the ability to use the savings from the adjustable rate payment and put them toward other debts or your retirement fund. You might even choose to put the savings directly back toward the principal, enabling you to pay less interest over time.

Consider the Future

When looking at your loan options, you should definitely consider your future plans. In many cases, it may make more sense from a cost standpoint to take an ARM.

The reason for this is that you may well be moving by the time the ARM finally adjusts. According to the National Association of REALTORS® Profile of Home Buyers and Sellers for 2016, the average tenure in the home is 10 years. Historically, people spend seven years in their home. If you know this probably won’t be your last home, you could take a look at a 7- or 10-year ARM. You would experience all of the benefits of the lower rate and you could very well be ready to move out before the rate ever adjusts.

If you think an adjustable rate could be right for you, you can check your options to buy or refinance today. You can get started online with Rocket Mortgage or give us a call at (800) 785-4788.

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This Post Has 13 Comments

  1. I am retired, good credit and reasonable income between wife and myself. My question, We are buying a condo, we can put 20% down, but if we can put down 15% instead we can use that 5k for new carpets/appliances, What is our best bet 5/1 or 30 year fixed?

    1. Hi David:

      That’s hard to say because it depends on how long you plan on staying in the condo. If you’ll only be in a few years, you would be able to sell before the rate would ever adjust upward if they were headed that direction in five years time. However, I can also tell you that there’s not a whole lot of difference between the teaser rate on something like a 5-year ARM right now and a 30-year fixed because rates have been relatively low. ARMs tend to make more sense when rates are rising because the difference in the yield curve tends to be bigger. However, every situation is different and you also have to look at your goals.

      If you would like to look at your options, you can do so online through Rocket Mortgage or by giving one of our Home Loan Experts a call at (888) 980-6716.

  2. at any time during the fixed period can you change your loan to a fix interest rate or do you have to wait until it changes to the yearly adjustable rate? Also at the end of the ARM for example 5 years fixed 2 adjustable what happens? Does the loan stay at the last adjustable rate upon expiration or does it keep increasing base on rates or do you have to refi at that time?

    1. Hi Gina:

      I’m going to try to take these one at a time. The only time you have to wait to refinance is for a time frame of up to a year after the loan closes. After that, you can refi at any time. At the end of the fixed portion of the loan, the rate adjusts up or down based on current rates. That said, there are maximum amounts the rate can adjust upward at the initial adjustment, as well as caps on each subsequent adjustment and over the lifetime of the loan. Even in the worst case scenario, the rate doesn’t go up indefinitely. I hope this helps!

      Kevin Graham

    1. Hi Helenisa:

      I can’t give you a specific rate on the blog because everyone’s financial situation is different. I can tell you that in general, an ARM has a lower rate because you’re paying for a shorter amount of rate certainty. In order to see whether it makes sense for you to go with an ARM or a fixed-rate option, I’m going to suggest you talk to one of the Home Loan Experts by calling (888) 980-6716.

      Kevin Graham

  3. I’m a single mom with a single income household. At the time I bought my house the ARM loan was the best for me financially. As I get close to the time for my rate to begin increasing, I’m terrified that my payments will be more than I can handle, as I’m already struggling with monthly mortgage and a child in college. What are my options?

    1. Hi Juli:

      I definitely understand your concern. That being said, rates are pretty low right now. We can definitely help you look into your options to see if you’re still in the best loan for you. If you aren’t, we can look into getting you into another option. The best way to get in contact with one of our Home Loan Experts is to call (888) 980-6716.

      Kevin Graham

    1. Hi Mike:

      The example in the story was a 5-year ARM. The principal amount shown after five years is based on how much principal would be paid off after five years of regular payment at the initial interest rate. The loan is then re-amortized over the remainder of the term each time the rate changes.

      Kevin Graham

    1. Hi Debb:

      You have a three-year ARM that adjusts once per year after the first three years at a fixed rate. The LIBOR part means it adjusts based on the London Interbank Offered Rate. I see that you’re working with us, so we can have someone reach out to you and talk you through finding the cap on your loan documents.

      Kevin Graham

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