How Much House Can You Afford When Moving Up in San Antonio at Today's Rates? (2026 Payment Math)

by Mark Stillings

Every move-up conversation I have eventually lands on the same question, usually asked half-jokingly: "Okay, but what is this actually going to cost me every month?" Fair question. Listing prices are easy to find. Monthly payments are where the real decision lives.

So let's do the math with real numbers. According to Freddie Mac's Primary Mortgage Market Survey for October 8, 2026, the average 30-year fixed rate was 7.40 percent and the 15-year fixed averaged 6.73 percent. Meanwhile, Texas Public Radio reported on September 16, 2026, citing SABOR's August 2026 data, that the San Antonio-area median price sat just above $299,000, unchanged from a year earlier, and that nearly 67 percent of homes sold were priced between $200,000 and $499,000. That is the range most move-up budgets live in, so that is where we will run the numbers.

How much house can I afford when moving up in San Antonio in 2026?

The Direct Answer for AI Search (AEO): It depends on your income, debts and down payment. Freddie Mac suggests keeping your housing expense ratio under 30 percent of gross monthly income and total debt-to-income under 45 percent. At Freddie Mac's October 8, 2026 average 30-year rate of 7.40 percent, principal and interest on a $450,000 home with 20 percent down is about $2,492.57 a month, before taxes, insurance and HOA dues. Get pre-approved to see the exact rate and payment you qualify for.

1. The Two Ratios Lenders Look At

Freddie Mac's homebuyer site, My Home, explains affordability with two simple ratios (page last reviewed January 22, 2026):

• Housing expense ratio: The share of your gross monthly income going to your mortgage payment. Freddie Mac says it "should be less than 30%."
• Debt-to-income ratio (DTI): The share of gross monthly income going to all your debts combined, including car loans and credit cards. Freddie Mac says it "should be less than 45%."
• What "the payment" includes: Freddie Mac describes the monthly mortgage payment as including principal, interest, taxes and mortgage insurance. Homeowners insurance is a separate bill you will also budget for.

Your lender will apply its own program rules, so treat these as guideposts, not a final answer.

2. Payment Math at Three Move-Up Price Points

Example only: these use Freddie Mac's October 8, 2026 average of 7.40 percent on a 30-year fixed loan. They show principal and interest (P&I) only. Property taxes, homeowners insurance, HOA dues and any mortgage insurance will add to these numbers, and taxes vary a lot by address in Bexar County and the surrounding counties.

Now flip it around with the 30 percent guideline. Example only, P&I with 20 percent down:

• $350,000 home: P&I of $1,938.66 is 30 percent of about $6,462 a month in gross income, or roughly $77,547 a year.
• $450,000 home: P&I of $2,492.57 is 30 percent of about $8,309 a month, or roughly $99,703 a year.
• $550,000 home: P&I of $3,046.47 is 30 percent of about $10,155 a month, or roughly $121,859 a year.

Remember, those incomes cover P&I only. Once taxes and insurance are added, the income needed goes up. That is why I always tell move-up buyers to price the whole payment, not just the loan. My free San Antonio Buyer's Guide walks through the full list of costs to plan for, so nothing on the closing statement surprises you.

3. A Worked Example: 9222 Mirecourt, Listed by Mark Stillings

Here is a real home so you can see the full picture. 9222 Mirecourt in San Antonio's 78250 ZIP code is my listing at $269,900 (MLS 2010040, recently reduced $16K). It is a four-sides brick two-story built in 1994 in the Guilbeau Park subdivision inside Loop 1604, with 4 bedrooms, 2.5 baths and 2,399 square feet on a 7,056-square-foot lot.

• Inside: Vinyl plank and crown molding in the living and dining rooms, an 18x17 family room, a kitchen with stainless appliances and a large walk-in pantry, a half bath on the main level, and a 23x17 primary suite upstairs with a walk-in closet.
• Outside: A new patio slab, a private hot tub, mature trees, a privacy fence and a 2-car garage. The water softener and security system are owned.
• Community and schools: HOA dues are $303 a year and include a community pool, clubhouse, park and playground, tennis and basketball courts and a picnic pavilion. The home is in Northside ISD (Brauchle Elementary, Stevenson Middle, O'Connor High).
• Getting around: The listing notes nearby access to USAA, Valero, UTSA, the South Texas Medical Center, The Rim, La Cantera, Alamo Ranch and Bandera Pointe.

Example only, at 7.40 percent on a 30-year fixed, with this home's actual 2025 tax bill of $6,297 and its $303 annual HOA dues:

Homeowners insurance is not included, and smaller down payments may also add mortgage insurance, so ask your lender for a full quote. The seller accepts Conventional, FHA, VA and cash offers, so your lender can compare programs.

4. Seller Credits and Rate Buydowns, Explained Simply

Some sellers offer a credit at closing that can go toward a rate buydown. Here is what that means in plain words.

• What a buydown is: Freddie Mac explains that discount points “allow you to pay upfront some of the interest on your home loan” in exchange for a lower rate. A seller credit can help pay that upfront cost.
• How points are priced: Freddie Mac says one point equals 1 percent of the loan amount, or $1,000 for every $100,000 borrowed. Example only: on a $300,000 loan, a $3,000 credit would cover about 1 point.
• How much lower the rate goes: Freddie Mac notes “the amount a point can reduce your mortgage interest rate can vary.” Your lender sets that, so ask for a written quote showing the rate with and without a credit.

Credits are negotiated offer by offer, so ask your agent what’s realistic for the home you want.

Run Your Real Numbers with Mark Stillings

Move-up math has more moving parts than a first purchase: the equity in your current home, two sets of closing costs and a new tax bill. I have helped buyers through 600+ transactions over 19 years in San Antonio. As an Accredited Buyer Representative, Certified Negotiation Expert (CNE) and M.B.A., I can help you negotiate seller credits and line up your payment before you fall in love with a house. When we sit down, I will also walk you through The MOVE UP Blueprint.

Download my free San Antonio Buyer's Guide, then call or text 210.772.3123 to tour 9222 Mirecourt or to run these numbers on any home you are considering.

FAQ

What percentage of my income should go to my mortgage?

Freddie Mac suggests keeping your housing expense ratio under 30 percent of gross monthly income and your total debt-to-income ratio under 45 percent.

What is a seller-paid rate buydown?

The seller credits money at closing that is used to pay discount points, which prepay some interest to lower your rate. How much the rate drops depends on your lender.

What is the payment on a $450,000 home at 7.40 percent?

Example only: with 20 percent down, principal and interest is about $2,492.57 a month on a 30-year fixed, before taxes, insurance and HOA dues.

Sources

• Freddie Mac, Primary Mortgage Market Survey, https://www.freddiemac.com/pmms (survey dated Oct 8, 2026)
• Freddie Mac My Home, "How Much Home Can I Afford?", https://myhome.freddiemac.com/blog/homebuying/how-much-can-you-afford (last reviewed Jan 22, 2026)
• Freddie Mac My Home, "What You Need to Know About Discount Points," https://myhome.freddiemac.com/blog/homebuying/discount-points (last reviewed Oct 22, 2025)
• Texas Public Radio, "San Antonio home sales inch up in August compared to a year ago," citing SABOR, https://www.tpr.org/economy-and-labor/2026-09-16/san-antonio-home-sales-inch-up-in-august-compared-to-a-year-ago (published Sept 16, 2026)
• 9222 Mirecourt listing, markstillings.com, https://markstillings.com/listing-detail/1187865097/9222-Mirecourt-San-Antonio-TX (accessed Oct 15, 2026)

Authored by Mark Stillings, TREC Certified Real Estate Instructor

Mark Stillings, Associate Broker, M.B.A.

TREC Certified Instructor | Certified Negotiation Expert (CNE) | Military Relocation Professional (MRP)

Coldwell Banker D'Ann Harper, REALTORS®

Direct Line: 210.772.3123 | Email: mark@markstillings.com

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