Adjustable-Rate Mortgages in 2026: What to Check Before You Take the Lower Rate

Adjustable-rate mortgages made up 10.5 percent of mortgage applications in the weeks ending October 9 and October 16, 2026, according to the Mortgage Bankers Association, as the average 5/1 ARM rate ran close to a full percentage point below the 30-year fixed rate. An ARM trades a lower starting rate for a rate that resets on a schedule, so the decision rests on four things you can check before you sign: the index and margin, the caps, how the lender qualifies you, and the notices you will receive before each change. Here is each one, with the figures as of October 2026.

Key takeaways

• In the MBA survey for the week ending October 16, 2026, the average 5/1 ARM contract rate was 6.46 percent with 1.11 points, against 7.41 percent with 0.75 points for a 30-year fixed conforming loan, and ARMs were 10.5 percent of applications.
• Conforming ARMs adjust off the 30-day Average SOFR published by the Federal Reserve Bank of New York, which stood at 3.88787 percent on October 22, 2026, plus a fixed margin of no more than 3 percentage points.
• Caps are written as three numbers, such as 2/1/5: the most the rate can rise at the first adjustment, at each later adjustment, and over the life of the loan.
• Regulation Z requires a separate notice 210 to 240 days before the first adjusted payment is due, and a notice 60 to 120 days before any later payment change.
• Lenders qualify a 5/1 ARM at the higher of the fully indexed rate or the note rate plus the first cap, so a 6.46 percent start rate with a 2-point cap is tested at 8.46 percent; the lower start rate does not loosen the approval.

Why are more borrowers choosing ARMs in late 2026?

Because the gap between ARM and fixed rates is close to a full point. In the MBA Weekly Mortgage Applications Survey released October 21, 2026, the average contract rate for a 5/1 ARM with an 80 percent loan-to-value ratio was 6.46 percent with 1.11 points, including the origination fee, while the 30-year fixed conforming rate was 7.41 percent with 0.75 points. "The ARM share held steady at 10.5%, as ARM rates remained almost a full percentage point lower," said Joel Kan, the association's deputy chief economist, giving "qualified borrowers a lower rate option to purchase a home."

Two details sit inside those averages. The ARM carried more points than the fixed loan, 1.11 against 0.75, which is a cost paid at closing (see discount points versus lender fees). And the fixed rate itself is at a 2026 high: Freddie Mac's 30-year average was 7.40 percent on October 15, 2026, and the MBA reported purchase applications 18 percent below the same week a year earlier. The figures in this guide are current as of October 22, 2026.

How does an adjustable-rate mortgage work in 2026?

An ARM holds one rate for an initial period, then resets at set intervals to an index plus a margin, subject to caps. The Consumer Financial Protection Bureau describes the new rate as "based on the new index plus a set margin," where the index tracks broader interest rates and the lender sets the margin. The basics are in our guide to fixed versus adjustable-rate mortgages; this section covers the figures that apply today.

The index. ARMs sold to Fannie Mae and Freddie Mac use the 30-day Average SOFR, a compounded average of the Secured Overnight Financing Rate that the Federal Reserve Bank of New York publishes each business day. On October 22, 2026 the 30-day Average SOFR was 3.88787 percent, with overnight SOFR for October 21 at 3.88 percent. The Fed's September 2026 increase is already in that figure, because SOFR tracks the Fed's target range.

The margin. The lender's margin is fixed for the life of the loan. Freddie Mac requires a margin of at least 100 and no more than 300 basis points on the SOFR ARMs it buys, and Fannie Mae's Selling Guide caps the margin at 300 basis points.

The fully indexed rate. Index plus margin, rounded to the nearest one-eighth of a percent under Fannie Mae's rules. With the October 22 index of 3.88787 percent and an illustrative 2.75 percent margin, the fully indexed rate is 6.63787 percent, which rounds to 6.625 percent. That is the rate an ARM originated today would carry after its fixed period if the index never moved.

The lookback and the floor. Fannie Mae sets each new rate from the most recent index value available 45 days before the change date, and the rate can never fall below the margin, whatever the index does. For 3-year and 5-year ARMs, Fannie Mae also limits how far the starting rate can sit below the fully indexed rate at origination: the difference "must not exceed 3%."

What do 5/6, 5/1, and 7/6 mean?

The first number is the years the rate is fixed; the second is how often it adjusts afterward, in months for a 5/6 (every six months) and in years for a 5/1 (once a year). The SOFR ARMs Fannie Mae and Freddie Mac buy are 3/6, 5/6, 7/6, and 10/6 products, while many lenders and surveys still use the older 5/1 and 7/1 labels for the same fixed periods. Fannie Mae requires the first adjustment to arrive at the end of the fixed period, 60 months in for a 5-year ARM.

What do the caps on an ARM limit?

Caps limit how far the rate can move at each adjustment and over the life of the loan, and they are stated as three numbers. A common structure on a 5/6 ARM is 2/1/5: no more than 2 points up at the first adjustment, no more than 1 point at each later adjustment, and no more than 5 points above the start rate ever. Fannie Mae requires every ARM plan to have both lifetime and per-adjustment limits, with the lifetime limit applying to increases only and the per-adjustment limit applying to increases and decreases. The CFPB adds that initial and later changes may carry different caps, and that some ARMs also limit how far the rate can fall.

The table shows what a 2/1/5 cap means in dollars on a $400,000 5/1 ARM at the October 16 average of 6.46 percent. Principal and interest only; taxes, insurance, and any mortgage insurance are extra. After the first adjustment the payment is recalculated on the remaining balance, about $374,000, over the remaining 25 years. The lifetime-cap row uses that same balance and term for comparison; under a 2/1/5 cap a 5/1 ARM cannot reach that rate before its fourth adjustment, in year 9, when the balance would be lower.

At the 6.46 percent start rate the payment is $2,518 a month for the first five years; if the rate rises the full 2 points at the first adjustment, the payment on the remaining balance becomes $3,004, and at the 11.46 percent lifetime cap it would be $3,793 on that same balance and term. For comparison, the same $400,000 at the 30-year fixed average of 7.41 percent costs $2,772 a month in principal and interest for all 30 years. The honest comparison is not year one against year one; it is the fixed payment against the range the ARM can reach, and the CFPB's advice is to find out "how high or low your interest rate and monthly payments can go with each adjustment" before signing rather than counting on selling or refinancing before the first reset.

How do lenders qualify you for an ARM?

At a rate higher than the start rate, in most cases. Under the ability-to-repay rule, 12 CFR 1026.43(c)(5)(i), a lender must underwrite an ARM using "the fully indexed rate or any introductory interest rate, whichever is greater," with fully amortizing payments. For a loan to count as a general qualified mortgage, the rule goes further: the payment is calculated at "the maximum interest rate that may apply during the first five years after the date on which the first regular periodic payment will be due."

Fannie Mae's qualifying rules apply that test by product. An ARM with a fixed period of 3 years or less is qualified at the maximum rate that could apply in the first five years. A 5-year ARM is qualified at the greater of that maximum (the note rate plus the first cap) or the fully indexed rate; in Desktop Underwriter that reads as the greater of the fully indexed rate or the note rate plus 2 percent. A 7-year or 10-year ARM is qualified at the note rate, unless the loan is a higher-priced mortgage under Regulation Z, in which case the greater of the note rate or the fully indexed rate applies.

At the October 16 average, then, a 5/1 ARM is underwritten 2 points above its start rate, while a 7/1 is underwritten at the rate on the note. The lower start rate changes the first five years of payments; it does not change the debt-to-income test in the lender's favor.

What notices must you receive before an ARM adjusts?

Three sets, at application, at the first reset, and at every later payment change. When you apply, 12 CFR 1026.19(b) requires the lender to give you the Consumer Handbook on Adjustable Rate Mortgages and a program disclosure for each ARM program you ask about. The disclosure covers the index and where to find it, how the rate and payment are calculated, whether the start rate is discounted, how often adjustments happen, the caps, and a worked example on a $10,000 loan. The Loan Estimate then shows how often the rate can change, when it first changes, the maximum rate, and the first date that maximum could be reached, with the index, margin, and limits in its adjustable interest rate table; our guide on reading a Loan Estimate walks through the form.

Before the first reset, 12 CFR 1026.20(d) requires a notice "at least 210, but no more than 240, days before the first payment at the adjusted level is due." It must be a separate document, it may show estimates based on the index within fifteen business days before the notice, and it must list alternatives such as refinancing or selling and give a contact number and housing counseling resources. If the first adjusted payment falls within 210 days of closing, that notice comes at closing.

Before every later change that moves the payment, 1026.20(c) requires a notice "at least 60, but no more than 120, days before the first payment at the adjusted level is due." That notice carries a table with the current and new rate, the current and new payment, and the date the new payment is due, and an explanation of the index, margin, and any caps applied. ARMs with terms of one year or less are exempt from both notices, and loans that adjust every 60 days or more often get a shorter 25-day minimum.

On a 5/6 ARM closed in October 2021, for example, the first payment was due December 1, 2021, the 60 fixed payments run through November 2026, and the first adjusted payment arrives at the start of 2027, so the 210-to-240-day notice was due in late spring 2026 and the 60-to-120-day notice in the autumn.

What if your ARM was indexed to LIBOR?

It now adjusts off a SOFR-based rate. U.S. dollar LIBOR panels ended after June 30, 2023, and the Federal Reserve Board's rule under the Adjustable Interest Rate (LIBOR) Act replaced LIBOR in contracts that lacked workable fallback language with benchmark replacements based on SOFR. Older ARMs commonly adjusted once a year off one-year LIBOR, so a borrower whose loan was written that way is now on a replacement index. The adjustment notice your servicer sends must name the index used and where it is published, which is the place to confirm what your loan now follows.

How do you compare an ARM offer with a fixed-rate offer?

On the same day, on more than the start rate. Four checks cover most of the difference:

1. The A.P.R. is a composite, not a forecast. Under Regulation Z's official commentary to 1026.17, an ARM's disclosed A.P.R. is built from the initial rate "for as long as it is charged" and then "the rate that would have been applied using the index or formula at the time of consummation." It shows what the loan would cost if the index stayed where it was on the day of the quote. It cannot tell you where the index will be in five years; see APR versus interest rate.
2. The points. The October averages carried 1.11 points on the ARM against 0.75 on the fixed loan. A point is 1 percent of the loan amount paid at closing, so the ARM's up-front cost is part of the comparison.
3. The maximum payment at the first reset and over the life of the loan. Ask for both figures in dollars, as the table above shows, and compare them with the fixed payment.
4. Your horizon. An ARM's advantage lasts for the fixed period. Refinancing later costs money and depends on rates and your finances at the time, as our guide to refinance break-even points explains, and the CFPB warns against counting on a sale or refinance to escape the reset.

Quotes expire, often within one to three business days, so the comparison has to be made across offers dated the same day; see why rate quotes expire and mortgage rate locks.

How does a HomeTurf auction handle ARM requests?

On HomeTurf you can set one of your two loan structures, called lanes, to a 5/1, 7/1, or 10/1 ARM and run it beside a fixed-rate lane, so the same N.M.L.S.-verified, state-licensed lenders can quote both inside one window of 12, 24, 36, or 48 hours. Offers are grouped by lane, and each shows its rate, A.P.R., fees, and points exactly, so the ARM offers compare with each other and the fixed offers compare with each other. Lenders see ranges in Pre-Approval auctions, the exact rate and A.P.R. to beat plus ranges in Beat My Rate auctions, and exact property and loan figures in Purchase and Refinance auctions, because accurate offers depend on them. HomeTurf is a technology marketplace, not a lender or loan originator.

Before you select an ARM offer, ask the lender for the index, margin, and caps and confirm them on its Loan Estimate; the auction shows the price of each offer, and the lender's disclosures show the terms behind it. HomeTurf does not lock rates or guarantee any rate; any lock happens afterward with the lender you choose. You stay anonymous while lenders bid, HomeTurf does not pull your credit, and your credit range is self-reported. Lenders cannot pay for placement, and HomeTurf never selects, ranks as best, or recommends a lender. Only the lender you choose receives your contact details, and it must reach out within 36 hours.

Frequently asked questions

What is the SOFR rate used for ARMs right now?

The 30-day Average SOFR was 3.88787 percent on October 22, 2026, and overnight SOFR was 3.88 percent on October 21, 2026, according to the Federal Reserve Bank of New York, which publishes both each business day shortly after 8:00 a.m. Eastern. A conforming ARM's new rate is that average, as of the lender's lookback date, plus the loan's fixed margin, rounded to the nearest one-eighth of a percent and subject to the caps.

How much notice do you get before an ARM payment changes?

Regulation Z requires a separate notice at least 210 and no more than 240 days before the first payment at the adjusted rate is due, and a further notice at least 60 and no more than 120 days before any later payment change. The first notice may use estimates and must list alternatives such as refinancing or selling; the later notices show the current and new rate and payment in a table. ARMs with terms of one year or less are exempt.

Can an ARM rate go down at an adjustment?

Yes. The new rate is the index plus the margin, so if the index has fallen since the last adjustment, the rate falls with it, subject to two limits. Fannie Mae's rules apply the per-adjustment cap to decreases as well as increases, and the rate can never fall below the margin itself, so an ARM with a 2.75 percent margin cannot go below 2.75 percent whatever the index does.

Is a 7/1 ARM easier to qualify for than a 5/1 ARM?

Often, because of the qualifying rate rather than the start rate. Under Fannie Mae's rules a 5-year ARM is qualified at the greater of the fully indexed rate or the note rate plus the first cap, while a 7-year or 10-year ARM is qualified at its note rate unless the loan is a higher-priced mortgage. A 5/1 at 6.46 percent with a 2-point first cap is therefore tested at 8.46 percent, and a 7/1 at 6.46 percent is tested at 6.46 percent.

Does an ARM's A.P.R. tell you what you will pay after the fixed period?

No. The disclosed A.P.R. on an ARM is a composite built from the start rate for the fixed period and the rate the index and margin would have produced on the day the loan closed for the rest of the term. It is useful for comparing two ARM offers made on the same day, because it folds in points and fees, but it does not predict where the index will be at the first reset.

Price the whole loan, not the first five years

An ARM at a point below the fixed rate is a real difference in the early years, and the caps, the index, the margin, and the notice rules decide what happens after them. Check all four before you choose, and compare the fixed payment against the range the ARM can reach. When you are ready to see what verified lenders will offer on both structures, you can Start Your Auction. HomeTurf is a technology marketplace, not a lender, and it is free for borrowers.

Remember that this is general information, not financial advice, and every situation is different.

Sources

• Mortgage Bankers Association, Weekly Mortgage Applications Survey, release of October 21, 2026 for the week ending October 16, 2026: mba.org
• Federal Reserve Bank of New York, SOFR Averages and Index: newyorkfed.org
• Fannie Mae, Selling Guide B2-1.4-02, Adjustable-Rate Mortgages (ARMs): selling-guide.fanniemae.com
• Fannie Mae, Selling Guide B3-6-04, Qualifying Payment Requirements: selling-guide.fanniemae.com
• Freddie Mac, SOFR-Indexed ARMs: sf.freddiemac.com
• Freddie Mac, Primary Mortgage Market Survey, October 15, 2026: freddiemac.com
• Consumer Financial Protection Bureau, Regulation Z, 12 CFR 1026.20, rate adjustment notices: consumerfinance.gov
• Consumer Financial Protection Bureau, Regulation Z, 12 CFR 1026.19(b), ARM program disclosures: consumerfinance.gov
• Consumer Financial Protection Bureau, Regulation Z, 12 CFR 1026.43, ability to repay and qualified mortgages: consumerfinance.gov
• Consumer Financial Protection Bureau, Regulation Z, 12 CFR 1026.17 and official commentary on variable-rate A.P.R.: consumerfinance.gov
• Consumer Financial Protection Bureau, Regulation Z, 12 CFR 1026.37, Loan Estimate contents: consumerfinance.gov
• Consumer Financial Protection Bureau, What is an adjustable-rate mortgage (ARM)?: consumerfinance.gov
• Board of Governors of the Federal Reserve System, final rule implementing the Adjustable Interest Rate (LIBOR) Act, December 16, 2022: federalreserve.gov

HomeTurf is a technology marketplace, not a lender or loan originator. This content is for general information only and is not financial or legal advice.