ELI5: The 3/27 Adjustable-Rate Mortgage (ARM)

Advanced Definition
Last updated: Jul 27, 2023

ELI5: 3-27 ARM Explained

Imagine you have a cool remote control that can change the speed of your toy car. A 3-27 ARM is a bit like that remote control, but instead of a toy car, it's for your home loan. It's a type of adjustable-rate mortgage that gives you a fixed interest rate for the first three years and then switches to a different rate for the remaining 27 years. Don't worry – I'll explain it in simple terms using our toy car example!

The Toy Car Scenario

Let's say you have a toy car with different speed settings. Your toy car loan works similarly with a 3-27 ARM.

  • First Three Years: During the first three years, you set your toy car's remote control to "slow" mode, which is like the fixed-rate period of a 3-27 ARM.

  • Remaining 27 Years: After the first three years, you switch your toy car's remote control to "fast" mode, and it zooms around at a different speed, just like the adjustable-rate period of a 3-27 ARM.

Making Sense of the 3-27 ARM

Okay, let's break it down further:

First Three Years: Fixed Rate

For the first three years of your toy car adventure (the "3" part), you enjoy a fixed interest rate. It's like setting your toy car's remote control to "slow" mode, where you know exactly how much you'll pay each month.

Remaining 27 Years: Adjustable Rate

After those first three years, things change – just like switching your toy car to "fast" mode. The "27" part of the 3-27 ARM means that for the next 27 years, your interest rate can change periodically. It's like your toy car zooming around at different speeds.

Why Choose a 3-27 ARM?

You might wonder why anyone would want a 3-27 ARM for their toy car or home loan. Well, there are a few reasons:

  1. Low Initial Payments: The fixed-rate period offers lower and more affordable payments in the first three years, just like cruising around in "slow" mode.

  2. Short-Term Plans: If you plan to sell your house within the first three years, the 3-27 ARM can be a good choice because you'll enjoy the lower fixed rate and won't experience the adjustable rate.

  3. Flexibility: The adjustable-rate period allows for potential rate changes. If interest rates go down in the future, your payments might become even lower, like when you switch your toy car to "fast" mode and go even faster!

Comparing 3-27 ARM with Other Common Mortgages

Let's compare the 3-27 ARM with some other common mortgages to see how they differ. Just like how different toy cars have various features, mortgages have their own unique traits! Check out the comparison table below:

Mortgage TypeFixed PeriodAdjustable PeriodBenefits
3-27 ARM3 years27 years- Low initial payments for the first 3 years
- Potential for lower rates in the adjustable term
- Suitable for short-term homeownership plans
30-Year Fixed30 yearsN/A- Stable payments throughout the entire term
- Predictable monthly payments
- Good for long-term homeownership plans
5/1 ARM5 years25 years- Fixed rate for 5 years, then adjustable
- Lower initial rate compared to 30-year fixed
- Potential for rate decrease in the future

Understanding the Comparison

  • 3-27 ARM: Offers a fixed interest rate for the first 3 years, and then the rate can change over the remaining 27 years. Good if you want low initial payments and have short-term plans.

  • 30-Year Fixed: Keeps the same interest rate throughout the entire 30-year term. Suitable if you prefer stable and predictable payments for the long term.

  • 5/1 ARM: Has a fixed rate for the first 5 years, followed by an adjustable rate for the next 25 years. A good option if you want a lower initial rate and are open to potential rate changes.

Remember, just like choosing the perfect toy car, finding the right mortgage depends on your needs and preferences. Always compare different mortgages, understand their features, and choose the one that fits your financial journey the best!


A 3-27 ARM is like a remote control for your toy car, offering you a fixed and predictable mode for the first three years and an adjustable mode for the remaining 27 years. It can be a suitable option if you want lower initial payments, have short-term plans for your home, or expect interest rates to change in the future. Just like playing with your toy car, understanding the different settings of the 3-27 ARM can make your financial journey smoother and more exciting!