Most Arizona buyers assume their mortgage interest will cut their tax bill. For a lot of them it will not. Since the standard deduction jumped, the deduction only helps when your interest plus other itemized deductions beat that flat number. At Freddie Mac's 7.03% average for the week of September 24, a $500,000 loan throws off roughly $35,000 of interest in year one. That clears the bar for a married couple. A $300,000 loan does not. Here is where the line sits for Scottsdale and Metro Phoenix buyers.

How the deduction works in 2026

You can deduct interest on up to $750,000 of home acquisition debt, but only if you itemize instead of taking the standard deduction. The limit is $375,000 if you are married filing separately. Loans from before December 16, 2017 can qualify for an older $1 million limit. IRS Publication 936 spells out both.

The standard deduction for 2026 is $16,100 for single filers, $32,200 for married couples filing jointly, and $24,150 for heads of household, according to the IRS 2026 inflation adjustments. Itemizing only wins if your mortgage interest, state and local taxes, charitable gifts, and other itemized items add up to more than that.

That is why the same mortgage saves one couple real money and another couple nothing. The loan is not the variable. The rest of the return is.

What the numbers look like on a Phoenix loan

The table shows approximate first year interest on a 30-year fixed loan at 7.03%, compared with the 2026 standard deduction. Interest falls a little each year as the balance drops, so year one is the best case. Taxes vary by household, so treat this as a test, not tax advice.

Two things jump out. First, a married couple with a $400,000 loan is under the joint standard deduction on interest alone. Second, being over the line does not mean you save the whole number. You save tax only on the excess. On the $500,000 loan that is $2,789 above the standard deduction, and at a 22% bracket that is about $614 a year. Real money, not a reason to pick a house.

You do not deduct your interest. You deduct the part that sits above the standard deduction.

Arizona helps and hurts here. Property taxes in the state are low, with the average effective rate near 0.51%, so you stack up less itemized tax than a buyer in Texas or New Jersey would. Our post on Arizona property taxes for homebuyers shows how that plays out on a real bill. That means Arizona buyers are more likely to sit near the standard deduction and less likely to clear it.

Timing matters too. The table shows twelve full months, but a buyer who closes in October pays interest for about three months in the first tax year. That first return is usually the weakest one for itemizing. A closing in January flips it, because you get almost a full year of interest in year one. If you have flexibility on a closing date, ask your tax preparer which calendar year favors you before you set it. Do not delay a purchase for this alone, since a week of rate movement can outweigh the tax effect.

Prepaid interest at closing counts as well. It is the interest from your closing date to the end of that month, and it shows up on your closing statement and your Form 1098.

Points, closing costs, and what else counts

Points you pay to buy your main home are often deductible in the year you pay them, if you meet the IRS tests. Points on a refinance are generally spread over the life of the loan. Origination charges, appraisal fees, and title fees are not interest, so they are not deductible in the same way.

If you are weighing a rate buydown on a purchase, this matters. A point that lowers your rate and is deductible has a slightly better payback than the raw math suggests, but only if you itemize. Our guide to closing costs when buying in Arizona lists which charges are which, and our post on how much house you can afford shows why the monthly payment is a better guide than the tax break.

Run your own numbers

Where the deduction stops

The deduction stops at $750,000 of loan balance for most new buyers. If you take out a $1,000,000 jumbo loan in Paradise Valley or North Scottsdale, interest on the amount above $750,000 is not deductible. The bank does not track that split for you. Your Form 1098 shows all of your interest, and you or your tax preparer have to do the allocation.

A few more edges worth knowing:

• HELOC interest. It is deductible only when the money buys, builds, or substantially improves the home that secures the loan. Paying off credit cards with a HELOC does not qualify.
• Cash-out refinances. The same rule applies. The cash you use on the house is treated differently from the cash you spend elsewhere. Our post on cash-out refinance taxes in Arizona walks through it.
• Second homes and rentals. A second home can qualify under the limit. A rental follows different rules and is reported on its own schedule.
• Mortgage insurance. IRS Publication 936 said the mortgage insurance premium deduction had expired as of its last revision. Tax law has been changing, so ask your preparer what applies to your 2026 return.

For state treatment, the Arizona Department of Revenue publishes current forms and guidance at azdor.gov. Check there or with a tax professional before you assume the federal answer carries over.

What this means for Metro Phoenix buyers

Do not pick a loan for the tax break. Pick it for the payment, then let the deduction be a small bonus. Forbes Advisor listed the 30-year rate at 7.37% on September 29, and the Federal Reserve raised its target range by a quarter point to 3.75% to 4.00% this month. Rates are near a one year high. A tax saving of a few hundred dollars will not offset a rate that is a half point higher than it needs to be. That is where a broker earns the fee, because we price your file across lenders instead of quoting you one number.

The Homes.com Phoenix housing market report is a good place to see current prices and days on market before you decide how much loan you need. When you are ready to see what is listed, the Arizona Luxury Property Search covers Scottsdale and the Valley. To see how a loan moves from application to closing, our process page lays out every step, and the loan programs page shows what we shop, from conventional to jumbo to non-QM.

Curious what your payment and first year interest would be? Start at pillarmortgagegroup.com, book a call, or fill in the form below. I will run it with you.

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