What is an Adjustable-rate Mortgage? Pros, Cons, & How it Works

A man thinking what is an adjustable rate mortgage

An adjustable-rate mortgage (ARM) offers a dynamic choice compared to its fixed-rate counterpart, adding a distinct element to borrowing money for a home. But for those considering their choices for becoming homeowners, it’s crucial to fully grasp how an ARM works.

In this blog, we dive deep into the concept of adjustable-rate mortgages, explaining how they function, their advantages, and their disadvantages.

what is an adjustable rate mortgage

What is an Adjustable Rate Mortgage (ARM)

An adjustable-rate Mortgage (ARM), also known as a variable-rate mortgage, is a type of mortgage loan wherein the interest rate and corresponding payment amount are subject to fluctuations.

While resembling a variable rate mortgage due to its potential for interest rate changes during the loan term, an ARM differs in the sense that the mortgage payment amount remains non-fixed. This means that as interest rates undergo alterations, your monthly payments will also adjust accordingly.

a graph showing an adjustable rate mortgage from 2010-2023

How Do Adjustable-Rate Mortgages (ARM) Work?

Adjustable-rate mortgages operate based on the prime rate, where your ARM rate is determined by a spread over your lender’s prime rate.

If the prime rate increases, your ARM rate will follow suit, resulting in the following effects on your mortgage:

  1. Immediate Increase in Interest Payment: With a rate hike, your next scheduled mortgage payment will include higher interest charges right from the start.
  2. Higher Scheduled Payment: Due to increased interest, your upcoming mortgage payment will be larger, requiring you to allocate more funds.
  3. Interest vs. Principal Allocation: While the portion of your payment devoted to the mortgage principal remains constant, fluctuations in interest rates can alter the share allocated to mortgage interest, affecting your payment distribution.

Understanding the functioning of adjustable-rate mortgages empowers borrowers to handle interest rate fluctuations and make informed financial decisions.

A man discussing the advantages of adjustable rate mortgage

Advantages of an Adjustable-Rate Mortgage

An adjustable-rate mortgage (ARM) offers several advantages, especially for those considering mortgage refinancing and strategic financial planning. Some notable benefits include:

1. Cost Efficiency Over Time

Historically, adjustable-rate mortgages tend to be more economical over the long term compared to fixed-rate alternatives, potentially resulting in lower overall interest payments.

2. Favorable Break Penalties

Should the need arise to sell your home or terminate your variable-rate mortgage contract, adjustable-rate mortgages typically entail lower break penalties compared to fixed-rate counterparts, offering greater flexibility.

3. Smooth Transition to Fixed-Rate

One of the distinctive perks is the ability to transition to a fixed-rate mortgage whenever desired, allowing borrowers to lock in a stable rate if market conditions warrant such a move.

4. Accelerated Mortgage Payoff

For those aiming to pay off their mortgage faster, an ARM can provide an advantageous platform, potentially enabling borrowers to make extra payments during periods of lower interest rates and reducing the principal more swiftly.

These advantages underscore the versatility of adjustable-rate mortgages, catering to diverse financial objectives and offering a range of potential benefits for borrowers.

a woman that is shock and got problems on her mortgage payments

Disadvantages of Adjustable-Rate Mortgage

While adjustable-rate mortgages (ARMs) present certain advantages, they also come with potential drawbacks that borrowers should consider, especially when switching to a fixed-rate mortgage. Here are key disadvantages to be aware of:

1. Rate Fluctuations and Payment Increases

In scenarios where interest rates experience an uptick, the borrower’s monthly payments will also rise accordingly. Since ARM mortgage rates are tied to the prime interest rate, a substantial rate increase could lead to a significant jump in your mortgage rate.

For instance, if the prime rate rises by 2%, your mortgage rate could escalate from 5% to 7%, amplifying both your interest rate and monthly payment.

2. Uncertain Future Payments

The variability of ARM rates introduces uncertainty about your future payments. The possibility of facing higher payments down the line could create financial strain, particularly if you haven’t factored these potential increases into your budget.

3. Limited Long-Term Predictability

Unlike fixed-rate mortgages that offer consistent interest rates and payments, ARMs lack the predictability needed for long-term financial planning. This unpredictability can make it challenging to budget effectively over the life of the mortgage.

4. Potential for Payment Shock

A sudden and substantial rate increase could lead to payment shock, where your monthly payments unexpectedly rise to levels that strain your financial resources.

Considering these disadvantages underscores the importance of evaluating your risk tolerance and long-term financial goals when deciding whether to pursue an adjustable-rate mortgage or switch to a fixed-rate mortgage for more stability and predictability.

a picture showing the difference between the two rates

Adjustable-Rate vs. Variable Rate Mortgage in Canada

When choosing between a variable rate and an adjustable-rate mortgage (ARM), homeowners often consider the potential for cost savings against higher fixed rates. However, the payment structure can significantly impact the overall advantage of these options.  

Adjustable-Rate Mortgage (ARM) 


Variable-Rate Mortgage (VRM) 


Payment amount changes with prime 


Payment amount doesn’t change with prime (interest and principal vary) 


Interest and principal amounts behave differently 


Interest amount affects principal amount 
Mortgage length (amortization) remains unaffected by interest 


Mortgage length adjusts with principal changes 
No trigger rate or point 


Includes trigger rate for potential length and balance increase 
Renewal risk? No; mortgage stays on track as scheduled 


Renewal risk yes; potential for increased payment or lump sum 

How you save more: rates up – mortgage stays on track or down – extra budget room 


How you save more: rates down – faster principal payoff 


Potential cost: increasing rates may strain budget 


Potential cost: payment shock at renewal, increased length or balance 


The decision between ARM and VRM entails assessing these differences and aligning them with your financial goals and risk tolerance.  


A hand adjusting a button

Example of an Adjustable Mortgage Rate

Imagine you currently hold an adjustable mortgage rate set at Prime + 0.20%. This implies that your mortgage rate is composed of your lender’s existing prime rate, with an additional 0.20% applied.

To grasp the impact of prime rate changes on your monthly mortgage payment, consider a $500,000 mortgage with a 25-year amortization.

Assuming the current prime rate is 5.95%, your adjustable mortgage rate would be 6.15%. If the prime rate were to rise by 0.50% to 6.45%, your adjustable mortgage rate would subsequently become 6.65%.

This change would translate into the following effects on your mortgage payment:

  • Original Mortgage Payment at 6.15% = $3,244
  • New Mortgage Payment at 6.45% = $3,344

This example highlights that a mere 0.50% increase in the prime rate could result in a $100 monthly upswing in your mortgage payment for a $500,000 mortgage.

a graph showing how adjustable mortgage rate increases and decreases

Rate and Frequency Caps in Adjustable-Rate Mortgage

Adjustable-rate mortgages (ARMs) incorporate rate and frequency caps, which restrict the extent and frequency of changes to interest rates and monthly payments.

These limitations can apply to individual adjustment periods or the entire loan term. Additionally, a cumulative interest rate change cap might be in place, known as a life cap.

For instance, an ARM might specify:

  • A maximum interval of 6 months or a year between rate adjustments.
  • A limit of 1% per adjustment or 2% annually in rate increases.
  • A provision capping the total interest rate increase at 6% throughout the loan’s duration.

The appeal of ARMs lies in their initial lower payments, making them attractive to borrowers who anticipate higher future income.

choosing which one

Why Choose an Adjustable Mortgage Rate?

Adjustable mortgages provide several additional benefits beyond maintaining a consistent amortization structure:

1. Gradual Payment Changes

With adjustable mortgages, changes in the prime rate only affect your upcoming scheduled mortgage payment. This contrasts with variable rate mortgages, where you might need to catch up with a larger payment upon renewal.

This gradual adjustment approach reduces the potential payment shock experienced with variable-rate mortgages at renewal, especially if rates remain high.

2. Convertibility to Fixed Rate

Adjustable mortgage lenders often offer the flexibility to convert to a fixed mortgage rate whenever you choose. This feature enables you to secure a fixed rate if you anticipate future rate increases. If rates decrease, you can take advantage of the lower rate and a subsequent reduction in your mortgage payment.

3. Lower Mortgage Penalties

Adjustable-rate mortgages typically come with lower mortgage penalties, often equivalent to just three months’ interest. In contrast, closed fixed-rate mortgages may involve more significant penalties based on the interest rate differential (IRD).

These advantages make adjustable mortgage rates appealing for those seeking flexibility, reduced payment shock, and potential cost savings in the long run.

An Old Man Thinking

Is an Adjustable Mortgage Rate Right for Me?

When evaluating whether an adjustable-rate mortgage aligns with your circumstances, consider these five essential points:

1. Flexibility of Budget

Assess your budget’s flexibility. An adjustable rate might be suitable if you can accommodate potential interest rate fluctuations within your cash flow. Conversely, a stable fixed-rate mortgage might be more fitting if you rely on a steady, fixed budget.

2. Risk Tolerance

Understand your comfort level with financial uncertainty. Adjustable rates might not faze you if you’re at ease with risk and market fluctuations. However, an adjustable-rate mortgage might not be the best choice if you prefer stability in your finances.

3. Current Market Conditions

Stay informed about prevailing economic trends. In times of rising inflation and interest rates, like today, the impact on your mortgage choice is significant. Being aware of market shifts is vital for informed decision-making.

4. Fixed-Vs-Variable Spread

Consider the difference between fixed and adjustable rates. A narrow spread often favors fixed rates, while a wider spread might make adjustable rates more appealing in terms of value.

5. Time Horizon

Evaluate your homeownership plans. If you foresee selling or moving within a few years, the lower penalty fees associated with adjustable rates for early contract termination could make them advantageous.

Remember, while experts can offer predictions, no one can precisely foresee future interest rates and economic shifts.

Explore The Ins and Outs of Adjustable-rate Mortgages Today

When purchasing a home, finding the right mortgage is a critical decision shaping your financial future. One option that often enters the conversation is the Adjustable-Rate Mortgage (ARM).

This financial tool offers an enticing alternative to the traditional fixed-rate mortgage, but you must understand its bolts and nuts, weigh the pros and cons, and make an informed decision that aligns with your long-term goals.

At data-contrast=”auto”>Lendtoday.ca, we’re here to assist you on your mortgage journey. Our team of experts specializes in customized mortgage solutions to your specific needs and goals. Feel free to reach out and explore how our services can provide you with the information and guidance you need to make the best decision for your future home.