San Antonio mortgage calculator
What a San Antonio mortgage costs each month, how long it runs, what it costs in total, and how much sooner it ends if you pay a little more. Built on monthly compounding and the 30-year fixed loan, and it charges you private mortgage insurance for exactly as long as the law lets a lender charge it, which is the line most calculators leave out.
Calculator
The purchase
20.0% down. The minimum on this price is $8,430. At 20% or more there is no mortgage insurance.
A US lender qualifies you on debt-to-income rather than at a stress-test rate, so this payment is the payment. What varies is the rate you are quoted: credit score, points paid at closing and the lender itself move it by more than half a point.
The contract length, not the amortization. At the end of it you renew at whatever rates are then available.
Paying it down faster
Most lenders cap annual prepayments at 10–20% of the original principal, and charge a penalty above it. Check your own commitment before planning around a large lump sum.
Where the money goes, year by year
Early payments are almost all interest. The crossover (the year principal finally exceeds interest) is the real shape of an amortized loan, and it is much later than most people expect.
Show the first two years of the schedule
| Payment | Amount | Interest | Principal |
|---|---|---|---|
| 1 | $1,500.13 | $1,316.95 | $183.18 |
| 2 | $1,500.13 | $1,315.87 | $184.26 |
| 3 | $1,500.13 | $1,314.79 | $185.34 |
| 4 | $1,500.13 | $1,313.71 | $186.42 |
| 5 | $1,500.13 | $1,312.62 | $187.51 |
| 6 | $1,500.13 | $1,311.52 | $188.61 |
| 7 | $1,500.13 | $1,310.41 | $189.72 |
| 8 | $1,500.13 | $1,309.30 | $190.83 |
| 9 | $1,500.13 | $1,308.18 | $191.95 |
| 10 | $1,500.13 | $1,307.06 | $193.07 |
| 11 | $1,500.13 | $1,305.93 | $194.20 |
| 12 | $1,500.13 | $1,304.79 | $195.34 |
| 13 | $1,500.13 | $1,303.65 | $196.48 |
| 14 | $1,500.13 | $1,302.50 | $197.63 |
| 15 | $1,500.13 | $1,301.34 | $198.79 |
| 16 | $1,500.13 | $1,300.17 | $199.96 |
| 17 | $1,500.13 | $1,299.00 | $201.13 |
| 18 | $1,500.13 | $1,297.82 | $202.31 |
| 19 | $1,500.13 | $1,296.64 | $203.49 |
| 20 | $1,500.13 | $1,295.45 | $204.68 |
| 21 | $1,500.13 | $1,294.25 | $205.88 |
| 22 | $1,500.13 | $1,293.04 | $207.09 |
| 23 | $1,500.13 | $1,291.83 | $208.30 |
| 24 | $1,500.13 | $1,290.61 | $209.52 |
Derived from the figures above, not a lender's statement. A real schedule also depends on your closing date and the lender's rounding.
An estimate from published figures, not a lender quote.
PMI is the number to watch, not the rate
If you put down less than 20% on a conventional loan the lender adds private mortgage insurance to the payment. It insures the lender, not you, and on the $280,999 Bexar County median sale price it works out like this. At 5% down (a $266,949 loan) a representative rate is about 0.67% of the loan a year, or $149 a month. Federal law makes the lender terminate it automatically when the scheduled balance first reaches 78% of the purchase price, which on a 30-year loan at 7.03% happens in month 142. That is 11.8 years and about $21,200 of payments that buy you no equity at all. At 3% down it is $198 a month and roughly $29,800.
Two things shorten it. You can ask the lender to cancel at 80% rather than wait for 78%, which is a right under the Homeowners Protection Act if you are current on the loan, and paying extra principal gets you there faster, because the trigger is the balance on the schedule rather than what the house is worth. The calculator above moves the termination month when you add an extra payment. The first-time buyer programs matter here too: the state's programs and the City of San Antonio's HIP loans, up to $30,000 for a household under its lower income limit, go toward the down payment, and a larger down payment is the one thing that removes the insurance altogether. A VA loan carries no mortgage insurance of this kind, which is worth knowing in a city with Joint Base San Antonio in it; this calculator does not model the VA's own funding fee.
The rate you are quoted is a personal number
This is the biggest difference from the Canadian pages on this site. There, CMHC publishes one premium schedule for the whole country and a lender either applies it or does not. Here the mortgage insurer prices you individually, mostly on credit score, and the same 5%-down loan can be quoted anywhere from about 0.4% to 1.3%. The bands used above are mid-market for a borrower around a 740 score. The loan rate itself moves too: Freddie Mac's survey had the 30-year fixed at 7.03% on 24 September 2026, against 6.30% a year earlier. Get a real quote before treating any of these totals as yours.
Monthly compounding, and why the Canadian number would be wrong
An American fixed-rate mortgage compounds monthly: the periodic rate is simply the annual rate divided by twelve. Canadian mortgages compound twice a year, which makes the same nominal rate slightly cheaper. On a $224,799 loan at 7.03% over 30 years the American payment is $1,500.13 and the Canadian convention would give $1,484.92: $15 a month, or about $5,500 over the life of the loan. This site runs both, and no page borrows the other country's arithmetic.
A biweekly plan is thirteen payments, not clever compounding
Paying half the monthly payment every two weeks means twenty-six half-payments a year, which is thirteen monthly payments' worth of money instead of twelve. On the benchmark loan with 20% down that takes a 30-year mortgage to about 24 years and saves roughly $79,300 in interest. There is nothing magic in it (it is simply paying about 8% more every year) and you can get the identical result by adding a twelfth of the payment to each monthly one, without a servicer's enrollment fee.
What this cannot tell you
The payment above is principal and interest, plus PMI where it applies. Your actual monthly bill will include property tax and homeowners insurance, which the lender will usually escrow: on a $280,999 house that is about $366 a month in tax at the 1.56% effective rate and roughly $250 in insurance, so about $2,116 all in at 20% down, before any flood policy, which a homeowners policy does not include. In Texas the tax line is the one to watch: that rate assumes you have filed for the homestead exemptions, which are not automatic, and the escrow account the lender opens at closing is sized to it. It is also worked out for a house in the City of San Antonio and Northside ISD; San Antonio ISD's rate is higher, and a house in Alamo Heights, Olmos Park or another of the separate cities inside San Antonio, or outside the limits in a special improvement district, pays a different bill. Add an association fee if the house has one, which more than a third of San Antonio owners pay. It also cannot tell you your closing costs, which in Texas run to the title company's escrow fee, split with the seller, a lender's title policy and its endorsements, an inspection, a survey or the seller's affidavit that the old one still holds, the county clerk's recording fees, and whatever the lender charges to originate the loan. There is no transfer tax to pay at all: the state constitution forbids one. For the full comparison against renting, use the rent versus buy calculator.
Sources
- San Antonio home sales rise 4% in August as prices hold steady · San Antonio Board of REALTORS · retrieved Supports: Bexar County: 2,068 home sales in August 2026, up 8.8% on the year, at a median price of $280,999, down 3.1%, and an average of $336,979, down 2.6%, The San Antonio area MLS: 3,104 sales, up 4%, at a median of $299,275 and an average of $372,989, released 10 September 2026, The release's table: an area median of $310,000 in August 2025 and $313,995 in August 2024, although its prose calls the median unchanged on the year, 5.87 months of inventory, 16,940 active listings and an average of 82 days on the market, 5,024 active residential rental listings at an average monthly rent of $1,832, down 2%, SABOR's membership serving Atascosa, Bee, Bexar, Frio, Karnes, Kendall, La Salle, Maverick, McMullen, Medina, Uvalde, Val Verde and Wilson counties
- South Texas market report: monthly releases · San Antonio Board of REALTORS · retrieved Supports: The monthly MLS releases for January through August 2026, reporting the San Antonio area and Bexar County and no City of San Antonio figure
- Zillow Home Value Index, all homes, middle tier, smoothed and seasonally adjusted, by city · Zillow Research · retrieved Supports: A typical home value of $247,453 for the city of San Antonio (region 6915) in August 2026, $253,000 in August 2025, so a fall of 2.2% over the year
- Zillow Home Value Index, single-family and condominium series, by city · Zillow Research · retrieved Supports: A typical single-family value of $249,206 in the city of San Antonio in August 2026, against $254,823 a year earlier, down 2.2%, A typical condominium value of $167,371 in the same month, against $174,092, down 3.9%, from the condominium file at https://files.zillowstatic.com/research/public_csvs/zhvi/City_zhvi_uc_condo_tier_0.33_0.67_sm_sa_month.csv
- San Antonio Rent Report, October 2026 · Apartment List · retrieved Supports: A median rent of $957 for a one-bedroom and $1,179 for a two-bedroom in the city of San Antonio, and $1,121 across all bedroom sizes, Rents down 0.2% over September and down 4.3% over the past 12 months, against -2.1% for the state
- Apartments for rent in San Antonio, TX: average rent · Apartment List · retrieved Supports: Average listed rents of $1,069 and up for a studio, $1,141 and up for one bedroom, $1,477 and up for two, and $1,887 and up for three or more
- FY 2026 fair market rents, San Antonio-New Braunfels, TX HUD Metro FMR Area · United States Department of Housing and Urban Development · retrieved Supports: FY 2026 fair market rents of $1,177 for one bedroom, $1,426 for two and $1,830 for three, as gross rents including utilities, Housing Choice Voucher programs in the metro using Small Area Fair Market Rents set by ZIP code
- Zillow Observed Rent Index, all homes plus multifamily, smoothed, by city · Zillow Research · retrieved Supports: An observed rent index of $1,386 for the city of San Antonio in August 2026, against $1,406 a year earlier, down 1.39%
- 2025 official tax rates and exemptions · Bexar County Tax Assessor-Collector · retrieved Supports: 2025 rates per $100: Bexar County 0.276331, Road and Flood Control Fund 0.023668, Hospital District 0.276235, City of San Antonio 0.541590, Northside ISD 1.004900, San Antonio ISD 1.155200, Alamo Community College District 0.149150, San Antonio River Authority 0.018300, Homestead exemptions of $5,000 or 20% for Bexar County, the Hospital District and the City; $3,000 and 20% for the Road and Flood Control Fund; $5,000 or 1% for the college district; $5,000 or 4% for the River Authority; $140,000 for Northside ISD; $140,000 and 0.01% for San Antonio ISD, San Antonio Municipal Utility District No. 1 at 0.20, twelve emergency service districts at up to 0.10, and 24 special improvement districts, 22 of them at 0.541590, The Downtown Public Improvement District at 0.15, and 0.09 on condominiums, Official tables from 2005 to 2025 and none yet for 2026, from https://www.bexar.org/1591/Tax-Rates
- 2024 actual tax rates and 2025 actual tax rates, as of 5 December 2025 · Bexar Appraisal District · retrieved Supports: The same 2025 rates to the sixth decimal, and each unit's 2024 rate beside it: the City, the county, the Road and Flood fund, the Hospital District, the college district and Northside ISD unchanged, and the River Authority up from 0.017870, Local option homestead exemptions not less than $5,000, and the Road and Flood fund's $3,000 homestead exemption, Redbird Ranch water districts at 1.00 per $100
- 2025 tax rate calculation worksheets: City of San Antonio · Bexar County Tax Assessor-Collector · retrieved Supports: A debt rate of 0.21150 per $100 within the City's 0.54159, leaving 0.33009 for maintenance and operations, The same 0.54159 adopted for the 2024 tax year
- Property tax exemptions · Texas Comptroller of Public Accounts · retrieved Supports: A school district residence homestead exemption of $140,000 under Tax Code section 11.13(b), Local option homestead exemptions of up to 20% of appraised value, and not less than $5,000, under section 11.13(n), A $3,000 residence homestead exemption from a county's farm-to-market or flood control tax under section 11.13(a)
- Valuing property: limitation on residence homestead value increases · Texas Comptroller of Public Accounts · retrieved Supports: A residence homestead's appraised value may not rise more than 10% a year once the owner has qualified in the preceding and current year
- Property tax protests and appeals · Texas Comptroller of Public Accounts · retrieved Supports: A protest deadline of 15 May or 30 days after the appraisal district mails the notice of appraised value, whichever is later
- 2020 block assignment files, Texas: unified school districts and places · United States Census Bureau · retrieved Supports: Read with the 2020 redistricting file's block populations, at https://www2.census.gov/programs-surveys/decennial/2020/data/01-Redistricting_File--PL_94-171/Texas/tx2020.pl.zip, Of the City of San Antonio's 1,434,625 residents in 2020: 468,901 in Northside ISD, 368,830 in North East ISD, 298,175 in San Antonio ISD, 59,802 in Harlandale ISD, 56,792 in Edgewood ISD and 45,376 in South San Antonio ISD, 298,175 of San Antonio ISD's 300,690 residents inside the city, and 468,901 of Northside ISD's 665,676
- Annual estimates of the resident population for incorporated places, 2020 to 2025 · United States Census Bureau, Population Estimates Program · retrieved Supports: A population of 1,548,422 for San Antonio on 1 July 2025, 1,548,411 of them in Bexar County and 11 in Medina County, A population of 2,160,088 for Bexar County on the same date
- 2025 Gazetteer files: places, Texas · United States Census Bureau · retrieved Supports: A land area of 498.979 square miles and a water area of 5.735 square miles for San Antonio city
- Extraterritorial Jurisdiction (ETJ) · City of San Antonio Planning Department · retrieved Supports: The ETJ as the unincorporated land within five miles of the City's boundaries and not within another city's limits or ETJ, The area in which the City may annex land, with the consent of the landowner or voter approval, Senate Bill 2038, effective 1 September 2023, establishing a petition and election process for releasing property from a city's ETJ
- ETJ planning · City of San Antonio Planning Department · retrieved Supports: Two Military Protection Areas, within five miles of Camp Bullis and the Lackland Training Annex, developed as a direct result of a 2017 state law curtailing unilateral annexation by Texas cities
- Annexation and growth management policy, adopted 31 August 2023 · City of San Antonio Planning Department · retrieved Supports: Senate Bill 6 (2017) curtailing the annexation powers of cities in counties of more than 500,000 people, such as San Antonio, and requiring landowner or voter approval, Elections called in 2018 for areas within five miles of Camp Bullis-Camp Stanley and Lackland Air Force Base-Medina Training Annex, where owners chose land use controls rather than annexation, Chapter 382 public improvement districts created by the county with the City's written consent as the most common special district request
- Public improvement districts and special districts · City of San Antonio Planning Department · retrieved Supports: Special districts in the City's ETJ, including Chapter 382 public improvement districts, also called special improvement districts, water control and improvement districts and fresh water supply districts, Districts created by the county at a landowner's request with the City's consent, conditioned through development agreements
- Our history · CPS Energy · retrieved Supports: The nation's largest public power, natural gas and electric company, serving more than 996,000 electric and 399,000 natural gas customers, $10.6 billion in revenue generated for the City of San Antonio since 1942, Acquired by the City of San Antonio on 24 October 1942
- Edwards Aquifer · San Antonio Water System · retrieved Supports: About 47%, some 154,000 acre-feet, of the water SAWS customers used in 2025 came from the Edwards Aquifer, Permitted withdrawals subject to cutbacks of zero to 44% in critical periods
- Water supplies · San Antonio Water System · retrieved Supports: In 1995 all of San Antonio's water came from the Edwards Aquifer; SAWS now manages 13 supply projects from seven sources
- Stage 3 watering rules · San Antonio Water System · retrieved Supports: Stage 3 rules in effect on 30 September 2026: landscape watering once a week, on the customer's day, from 5 to 10 a.m. and 9 p.m. to midnight
- Stormwater fee · San Antonio Water System · retrieved Supports: SAWS bills the City of San Antonio's stormwater fee on the City's behalf, Residential rates of $3.75 a month up to 2,750 square feet of impervious area, $4.94 to 4,220 square feet and $10.45 above it
- Solid waste rates and fees · City of San Antonio Solid Waste Management Department · retrieved Supports: Monthly totals of $19.76, $25.26 and $35.75 for the small, medium and large garbage cart, including the $3.00 solid waste and $2.00 parks environmental fees, The fee shown and collected on the CPS Energy bill, with no additional fee for the recycling and organics carts
- South Central Texas flood event, October 1998 · National Weather Service, Austin/San Antonio · retrieved Supports: 11.26 inches of rain at San Antonio International Airport on 17 October 1998, the most on any calendar day, and 13.35 inches in 24 hours, Rain along the Balcones Escarpment for up to 36 hours
- June 11 to 12, 2025 San Antonio area flood event · National Weather Service, Austin/San Antonio · retrieved Supports: 13 fatalities from flooding across the San Antonio area, 12 in the Beitel Creek basin and one in the Leon Creek basin, 15 vehicles swept into Beitel Creek from the Loop 410 frontage road near Perrin Beitel Road, 3.98 inches of rain in one hour at San Antonio International Airport, the highest hourly rate on record since 1934
- San Antonio, TX · Texas State Historical Association, Handbook of Texas · retrieved Supports: The flood of 9 and 10 September 1921, which put up to twelve feet of water downtown and killed at least fifty-one people, and the Olmos Dam and river bypass built after it
- Home, flood, wind: which policies do you need? · Texas Department of Insurance · retrieved Supports: Most home policies do not cover floods; a flood policy covers damage from rising water
- Joint Base San Antonio: economic impact, 2025 · Texas Comptroller of Public Accounts · retrieved Supports: Joint Base San Antonio as three operating locations: Fort Sam Houston, Lackland Air Force Base and Randolph Air Force Base, 74,713 direct employees in 2025, including 33,256 active-duty military personnel, A contribution of at least $53 billion to the Texas economy in 2025
- Primary Mortgage Market Survey, 24 September 2026 · Freddie Mac · retrieved Supports: A 30-year fixed-rate mortgage averaging 7.03%, up from 6.95% the week before and 6.30% a year earlier
- Texas homeowners insurance market overview · Texas Department of Insurance · retrieved Supports: A statewide average homeowners premium of $3,489 a year
- How much is homeowners insurance in San Antonio, TX? · Insure.com · retrieved Supports: An average San Antonio premium of $2,866 a year for $300,000 of dwelling cover, $100,000 of liability and a $1,000 deductible, updated 27 May 2026, An average of $2,222 a year for $200,000 of dwelling cover
- Texas homeowners insurance · NerdWallet · retrieved Supports: An average San Antonio premium of $4,565 a year for $500,000 of dwelling cover, $300,000 of liability and a $1,000 deductible, updated 20 February 2026
- Renters insurance in Texas · NerdWallet · retrieved Supports: An average San Antonio renters premium of $167 a year, $14 a month, for $30,000 of personal property, updated 23 September 2026
- Monthly homeowners' association and condominium fee, tables B25142 and B25143, 2024 American Community Survey 1-year estimates, San Antonio city · United States Census Bureau, via the Census Reporter API · retrieved Supports: A median monthly association fee of $60 among San Antonio owner-occupied units that pay one, 110,122 of 295,530 owner-occupied units, or 37.3%, paying such a fee, and 4,864 paying $500 or more a month
- Homeownership Incentive Programs (HIP) · City of San Antonio Neighborhood and Housing Services Department · retrieved Supports: HIP 80: $1,000 to $30,000 as a 0% interest, no-payment second loan, the first $15,000 forgiven over five years and the rest over ten, on an existing home up to $260,000 or a new one up to $284,000, with 2026 income limits of $56,350 for one person to $80,500 for four, HIP 120: $1,000 to $15,000, 75% forgiven over ten years and 25% perpetual, on an existing home up to $301,700 or a new one up to $332,800, with income limits of $84,500 for one person to $120,700 for four, A HUD-approved eight-hour homebuyer class, a home inside the city limits and a $500 minimum earnest money deposit
- HIP 80 and HIP 120 general information · City of San Antonio Neighborhood and Housing Services Department · retrieved Supports: Both programs for income-eligible first-time homebuyers buying a primary residence, which must pass a HIP property review and inspection, The remaining balance repaid in part on a change of ownership, a sale or a cash-out refinance, from this sheet and the HIP 120 sheet at https://www.sa.gov/files/assets/main/v/5/nhsd/documents/hip120-generalinformation.pdf
These are estimates built from published figures, not a lender quote, a pre-approval or financial advice. Rates, premiums and state and federal rules change; confirm anything you plan to act on with a mortgage professional and read the sourcing methodology.