Understanding Adjustable-Rate Mortgages (ARMs)

An adjustable-rate mortgage starts with a fixed interest rate for a specific period (typically 3, 5, 7, or 10 years), then adjusts periodically based on market conditions. While ARMs often offer lower initial rates than fixed-rate mortgages, they carry the risk of significant payment increases when rates adjust.

Common ARM Types

• 3/1 ARM: Fixed rate for 3 years, then adjusts annually
• 5/1 ARM: Fixed rate for 5 years, then adjusts annually (most common)
• 7/1 ARM: Fixed rate for 7 years, then adjusts annually
• 10/1 ARM: Fixed rate for 10 years, then adjusts annually
• 5/6 ARM: Fixed rate for 5 years, then adjusts every 6 months

How ARM Adjustments Work

When your ARM’s fixed period ends, your interest rate adjusts based on:

• Index Rate: A benchmark rate (like SOFR or Treasury rates) that reflects current market conditions
• Margin: A fixed percentage your lender adds to the index (typically 2-3%)
• Rate Caps: Limits on how much your rate can increase at each adjustment and over the life of the loan

Example: If you have a 5/1 ARM that started at 3.5% in 2020, and the current index is 5% with your margin of 2.5%, your new rate after adjustment would be 7.5%—potentially increasing your monthly payment by hundreds of dollars.

Real-World Impact: A $400,000 ARM at 3.5% has a monthly payment of $1,796. If it adjusts to 7.5%, your payment jumps to $2,797—an increase of $1,001 per month or $12,012 annually.

When Should You Convert Your ARM to Fixed-Rate?

Timing your conversion is crucial. Here are the key scenarios when converting makes sense:

6-12 Months Before Your First Adjustment

The ideal time to convert is before your ARM’s fixed period ends. Starting 6-12 months before your first adjustment gives you time to shop for the best rates, complete the refinance process, and potentially lock in a rate before your ARM adjusts. This proactive approach prevents payment shock and gives you negotiating leverage.

When Your ARM Rate Is Lower Than Fixed Rates

If your current ARM rate is still lower than available fixed rates, you may hesitate to convert. However, consider this: if your ARM is about to adjust significantly higher, even a slightly elevated fixed rate now may be lower than what your ARM will be after adjustment. Run the numbers to see your total costs over time.

After Your ARM Has Already Adjusted

If your ARM has already adjusted to a higher rate, converting to a fixed rate can lock in your current (or lower) rate before the next adjustment. Even if fixed rates are similar to your current ARM rate, the stability of fixed payments justifies the conversion.

When You Plan to Stay Long-Term

If your plans have changed and you now intend to stay in your home longer than initially expected, converting to a fixed rate makes sense. The longer your time horizon, the more valuable payment stability becomes.

When Interest Rates Are Rising

If the Federal Reserve is raising rates or expected to raise rates, converting sooner rather than later protects you from higher costs. Even if rates have already risen from when you got your ARM, locking in now prevents further increases from affecting you.

Pro Tip: Don’t wait until your ARM has adjusted multiple times. The earlier you convert, the more you save. Many homeowners who waited too long ended up converting at higher fixed rates than they could have secured earlier.

Fixed-Rate Mortgage Options After ARM Conversion

When converting from an ARM, you can choose from several fixed-rate options:

30-Year Fixed-Rate Mortgage

Best for: Homeowners who want the lowest possible monthly payment
Pros: Lowest monthly payment, maximum flexibility in budget
Cons: Higher total interest paid over life of loan
Consider if: You prioritize cash flow and want room in your budget for other goals

20-Year Fixed-Rate Mortgage

Best for: Those seeking a balance between payment and payoff speed
Pros: Build equity faster than 30-year, lower rate than 30-year
Cons: Higher monthly payment than 30-year
Consider if: You want to own your home sooner without the highest payment

15-Year Fixed-Rate Mortgage

Best for: Homeowners who can afford higher payments and want to build equity fast
Pros: Lowest interest rate, pay off mortgage in half the time, save massive amount in interest
Cons: Highest monthly payment, less budget flexibility
Consider if: You’re financially stable and want to be mortgage-free sooner

Interest Savings Example: On a $400,000 loan at 6.5%, a 30-year mortgage costs $509,000 in interest. A 15-year mortgage at 5.875% costs only $202,000 in interest—a savings of $307,000.

Special ARM Conversion Programs

Certain loan types offer streamlined conversion options:

FHA ARM to Fixed Conversion

If you have an FHA ARM, you can use the FHA Streamline Refinance program to convert to a fixed rate with minimal documentation, no appraisal, and lower costs. This is one of the easiest ways to convert from ARM to fixed.

VA ARM to Fixed Conversion

Veterans with VA ARMs can use the VA Interest Rate Reduction Refinance Loan (IRRRL) to convert to a VA fixed-rate mortgage. This program offers no appraisal, minimal documentation, and no out-of-pocket costs in many cases.

Ready to Lock in a Fixed Rate?

If you have an ARM and you’re concerned about future rate increases, converting to a fixed-rate mortgage provides the stability and predictability you need. As your Arizona mortgage expert, I can help you evaluate whether ARM conversion makes sense for your situation, provide competitive rate quotes, and guide you through the refinancing process from start to finish.

Don’t wait until your ARM adjusts and your payment increases dramatically. Contact me today for a free consultation to discuss your options and see how much you could save by locking in a fixed rate now.

Related Resources

• Refinancing in Arizona: Complete refinancing guide
• Conventional Fixed-Rate Loans: Learn about conventional mortgages
• FHA Streamline Refinance: Easy conversion for FHA ARM holders
• Understanding Closing Costs: What to expect when refinancing