Travis vs. Williamson vs. Hays County Property Tax Math on a $450K Austin Area Home
Before you sign with a builder in Leander or Kyle, here's the full math: city rate, school district, county levy, MUD surcharge, and homestead exemption applied to one purchase price across every m…
Before you sign with a builder in Leander or Kyle, here’s the full math: city rate, school district, county levy, MUD surcharge, and homestead exemption applied to one purchase price across every major Austin suburb.
August is when this decision gets expensive. Taxing entities across three counties are finalizing their 2026 levy rates right now. Builders are pushing Q3 incentive deadlines. Families anchored to the school enrollment calendar are signing contracts on new construction in Leander, Kyle, and Pflugerville without a clean number to work from. The builder rep quoted you an “estimated” tax rate. Your Realtor forwarded a link to the county appraisal district. You Googled it and found a forum thread from 2022 with numbers that no longer apply.
This piece does the actual math. One home, one purchase price—$450,000—six locations, every layer of the levy. We’re using the most current adopted rates available (FY2024–25, the proxy for your first full-year bill) and flagging where August 2025 adoptions may revise them. Read this before you sign anything.
Why Texas Property Taxes Are Different From Every Other State’s
Texas has no state income tax. The entire public infrastructure burden lands on the property tax bill: schools, roads, county courts, municipal services, emergency response. No softening mechanism. What you see on that annual notice is the full freight.
The levy is stacked. Your total rate is the sum of every taxing entity with jurisdiction over your parcel: county, plus independent school district (ISD), plus city, plus any special district on top. In older established neighborhoods, that’s usually three lines. In new-growth corridors built since 2005, it’s often four—and that fourth line, the Municipal Utility District (MUD) surcharge, is the one that routinely blindsides buyers. I’ve talked to people who closed on a new build in Cedar Park and genuinely did not know a MUD existed until their January notice arrived. That gap in buyer preparation is something we cover extensively in our moving & real estate coverage.
Two other things trip up buyers who move from other states. First, your tax bill is based on assessed value, not purchase price—but in Texas the appraisal district aims for 100% of market value. On a new construction home, plan for your first full appraisal to land at or near what you paid. Second, the homestead exemption is not automatic. You must file for it, and you must own the home on January 1 to qualify for that tax year. Buyers who close in November or December miss the exemption entirely for the first full calendar year. Nobody puts that in the sales brochure.
The 2023 legislative session changed a significant number in this equation. House Bill 3 raised the state school district homestead exemption from $40,000 to $100,000. Any tax estimate you’ve seen that predates this is materially wrong—and there are a lot of them still floating around. Any calculator, Zillow estimate, or forum post from before 2023 used the old floor. On a $450,000 home, the difference in taxable value for the ISD portion alone is $60,000. At a combined ISD rate of around $1.10 per $100, that’s $660 per year in real dollars that older estimates are overstating. Your neighbor’s 2022 tax bill is not a reliable guide to yours.
The Master Comparison Table: One $450K Home, Six Locations, Every Line Item
The following table uses the most current verified rates—FY2024–25 adopted levies—as proxies for the first full-year 2026 bill. August and September 2025 adoptions may adjust these modestly. All figures assume a $450,000 assessed value, homestead exemption applied, no MUD (MUDs are addressed separately in the next section).
Homestead exemption mechanics applied:
- State ISD exemption: $100,000 off assessed value for all locations → ISD taxable value: $350,000
- Travis County 20% optional homestead exemption: 20% of $450,000 = $90,000 reduction → County taxable value for Travis locations: $360,000
- City of Austin 10% optional exemption: 10% of $450,000 = $45,000 reduction → City taxable value for Austin location: $405,000
- Williamson County 1% or $5,000 (whichever is greater): $5,000 reduction → County taxable value for Williamson locations: $445,000
- Hays County: optional homestead exemption above the state floor not confirmed at the county level—verify at hayscad.net before calculating → County taxable value used here: $450,000
| Location | County Rate (per $100) | ISD Rate (per $100) | City Rate (per $100) | County Bill | ISD Bill | City Bill | Est. Annual Total | Est. Monthly |
|---|---|---|---|---|---|---|---|---|
| Austin / Travis Co. (AISD) | $0.3130 on $360K | $0.8987 on $350K | $0.4627 on $405K | $1,127 | $3,145 | $1,874 | ~$6,200–$6,800 | ~$517–$567 |
| Round Rock / Williamson Co. (RRISD) | $0.3680 on $445K | $0.9066 on $350K | $0.3476 on $450K | $1,637 | $3,173 | $1,564 | ~$6,500–$7,100 | ~$542–$592 |
| Cedar Park / Williamson Co. (Leander ISD) | $0.3680 on $445K | $1.0173 on $350K | $0.5200 on $450K | $1,637 | $3,561 | $2,340 | ~$7,800–$8,400 | ~$650–$700 |
| Pflugerville / Travis-Williamson (PISD) | $0.3680 on $445K | $1.1440 on $350K | $0.5149 on $450K | $1,637 | $4,004 | $2,317 | ~$8,200–$8,900 | ~$683–$742 |
| Kyle / Hays Co. (Hays CISD) | $0.3483 on $450K | $1.1092 on $350K | $0.5250 on $450K | $1,567 | $3,882 | $2,363 | ~$7,900–$8,500 | ~$658–$708 |
| Buda / Hays Co. (Hays CISD) | $0.3483 on $450K | $1.1092 on $350K | $0.3217 on $450K | $1,567 | $3,882 | $1,448 | ~$7,200–$7,800 | ~$600–$650 |
Rates are FY2024–25 adopted figures used as 2026 proxies. Annual total ranges reflect illustrative estimates based on these rates; individual line-item figures are illustrative at the midpoint. Verify final 2026 rates at TCAD (traviscad.org), WCAD (wcad.org), and Hays CAD (hayscad.net) after September 2025 adoptions. Pflugerville ISD straddles Travis and Williamson counties; Travis County exemption rates apply to Travis-side parcels. The table uses the Williamson County rate for Pflugerville as a representative proxy for the majority of recent new construction, which sits on the Williamson side.
The headline finding: the spread between the lowest and highest bill in this table is roughly $2,000 per year—before MUDs enter the picture. Cedar Park, Pflugerville, and Kyle rank highest. Buda and Austin come out nearly identical. Round Rock cuts well below Cedar Park. And Pflugerville, which many buyers target for its perceived affordability relative to Austin, costs more once the PISD rate gets added in. That last one consistently catches people off guard.
The Homestead Exemption Is Not Equal Across Counties
This is the fact most competing coverage skips. It’s also consequential enough to change which county actually looks cheapest once you run the real math.
Travis County’s 20% optional homestead exemption is the most generous local add-on in the metro. Applied to the county portion of your bill on a $450,000 home, it removes $90,000 from taxable value for county purposes—worth roughly $282 per year at current Travis County rates. Stacked with the City of Austin’s 10% exemption on the city portion, Travis County buyers receive relief that disappears entirely in any comparison showing only combined rates. Williamson County’s optional exemption tops out at 1% or $5,000, whichever is greater. On a $450,000 home, that’s $5,000 off the county taxable value—worth about $18 per year at current Williamson rates. The practical difference is real: buyers comparing a Travis County address to a Williamson County address using only the combined rate will systematically understate what Travis County’s bill actually comes out to after exemptions are applied. The headline number genuinely misleads here.
Hays County’s optional homestead exemption above the state minimum at the county level hasn’t been confirmed in current published rate materials. Verify the current status at hayscad.net before finalizing any Hays County tax estimate.
The filing deadline for homestead exemption is April 30 of the year following your closing. Close in August 2025, and you file before April 30, 2026. You must have owned and occupied the home as your primary residence on January 1, 2026, to qualify. Buyers who close in October, November, or December miss this—not permanently, but for that first tax year. On a $450K home, that means paying the full unexempted rate on your first bill. Late filing is allowed up to two years back, so you can recover it, but you’ll have already written the check.
One provision that appears in almost no buyer’s guide: the over-65 school tax ceiling. Once a homeowner turns 65, the school district portion of their bill freezes at that year’s level for as long as they occupy the home. More importantly, this ceiling is portable. Sell and buy a new home in Texas, and you can transfer the proportional benefit of the freeze to the new property. For buyers in their early sixties moving to new construction in Leander or Kyle, this portability provision is worth modeling explicitly with a tax professional before choosing a county. The dollar difference can be substantial, and the window to plan for it is before you sign—not after.
The MUD Surcharge: What Your Builder Rep Understated
A Municipal Utility District is a special-purpose government entity created under the Texas Water Code to finance infrastructure—water, wastewater, drainage, sometimes roads—in areas where no city utility service existed when development began. The developer creates the MUD, issues bonds, and those bonds are repaid through a separate property tax levy assessed on every home in the district.
MUD boundaries are parcel-specific, not city-wide. Two houses on the same street in Leander may have completely different MUD status. If a builder community broke ground after 2010 anywhere outside central Austin, it almost certainly sits in a MUD. And the MUD rate does not appear in the county’s published composite tax rate. It’s a separate line on your tax bill that buyers regularly see for the first time when the January notice arrives. For a deeper look at how these districts work and how to look up your specific parcel, see our coverage of what Austin MUD districts add to your property tax bill.
Rate ranges vary significantly by corridor. Williamson County MUDs in Cedar Park, Leander, and Georgetown typically run $0.25–$0.75 per $100 AV, depending on how recently the bonds were issued and how much infrastructure the district financed. Newer communities in the Leander and Cedar Park growth corridors are currently at the higher end of that range. Pflugerville MUDs sit in the $0.20–$0.50 range. Kyle and Buda MUDs run $0.30–$0.75+ per $100 AV, with some newer Buda subdivisions above $0.75 because Hays County MUDs issued larger bond packages to cover road infrastructure in addition to utilities.
Applied to your $450K home, the dollar impact is not trivial:
| MUD Rate | Annual Surcharge on $450K Home |
|---|---|
| $0.25 per $100 | $1,125 |
| $0.40 per $100 | $1,800 |
| $0.50 per $100 | $2,250 |
| $0.75 per $100 | $3,375 |
A $0.50 MUD rate—a reasonable midpoint for an active Williamson or Hays County district in a community built in the last ten years—adds $2,250 per year to whatever the master table shows. Applied to Cedar Park (Leander ISD), which already runs $7,800–$8,400 annually without a MUD, a $0.50 rate pushes the real bill above $10,000. At that point you are not getting a suburban discount.
Builder reps will tell you MUD rates decline as bonds are retired, and that’s true. Most MUDs fully retire their bonds within 20–25 years, after which the district either dissolves into the city or continues at a nominal maintenance rate. Buy in year one of a community that issued bonds in 2024 and you’re at peak rate. Buy a resale in a community built in 2000 and the MUD may have already retired. That distinction is worth knowing, and it almost never comes up in the sales office.
To look up whether your specific address carries a MUD, run the property address through the WCAD (wcad.org), TCAD (traviscad.org), or Hays CAD (hayscad.net) tax estimator and look for additional taxing entity lines beyond the standard county/ISD/city three. Cross-reference the TCEQ Municipal Utility District registry, which lists all registered MUDs by county with contact information for the district manager. That manager can confirm the current adopted rate. Under Texas Property Code §49.452, sellers must disclose MUD membership before contract execution. Buyers must sign an acknowledgment. Ask your agent for the MUD disclosure addendum before you make an offer—not after. If they say they don’t know what that is, find a different agent.
School District Rates: The Dominant Line Item on Your Bill
The ISD levy is the largest single number on every Austin-area property tax bill. It’s often twice the county rate. Parents choosing a school district are simultaneously choosing a tax rate—and the math is not proportional to school quality or reputation.
Ranked by estimated combined Maintenance and Operations (M&O) plus Interest and Sinking (I&S) rate on verified FY2024–25 figures:
| ISD | Combined Rate (per $100) | Annual ISD Bill on $350K taxable |
|---|---|---|
| Pflugerville ISD | ~$1.1440 | $4,004 |
| Hays CISD | ~$1.1092 | $3,882 |
| Leander ISD | ~$1.0173 | $3,561 |
| Round Rock ISD | ~$0.9066 | $3,173 |
| AISD | ~$0.8987 | $3,145 |
ISD taxable value after $100,000 state homestead exemption applied to $450,000 assessed value.
The spread between AISD and Pflugerville ISD on the ISD line alone is $859 per year. It’s almost entirely invisible to buyers who focus on the combined rate rather than breaking down the stack. Why do PISD and Hays CISD sit at the top? The reason is structural. Both districts issued large bond packages to fund school construction during the rapid growth of the last decade. The I&S (debt service) portion of the rate funds bond repayment. State school finance law—shaped by SB 2 and HB 3, both enacted in 2019—has held down M&O rates across districts but doesn’t constrain I&S rates the same way. Growth-era bond debt produces elevated rates that won’t normalize on the same timeline as operating levies. Pflugerville ISD’s I&S rate reflects the direct cost of building schools fast enough to absorb population growth. The buyer carries that cost annually.
A specific note on Buda: Buda and Kyle share Hays CISD, so the ISD rate is identical for both. What separates them is the city rate. Buda’s $0.3217 city rate is the lowest in this metro comparison—more than $0.20 per $100 below Kyle’s rate. On a $450,000 home, that’s roughly $915 per year in city-levy savings for Buda over Kyle, all else equal. For a buyer who’s genuinely neutral between the two, that difference is worth taking seriously.
Do the Suburbs Actually Save You Money? Commute and Insurance
The tax comparison is necessary but not sufficient. A buyer who saves money on property taxes in Kyle but spends considerably more on fuel, vehicle depreciation, and tolls may have made a bad trade—and a lot of buyers don’t run that second calculation until after they’ve signed.
Before committing to a specific suburb, anyone working downtown five days a week should calculate round-trip mileage from the specific address, multiply by the IRS standard mileage rate for the current year, and compare that figure against the annual tax savings shown above. For Kyle and Buda commuters on IH-35, the direction of that math is frequently not what they expected.
Current average annual homeowners insurance premiums on a $450,000 home (standard HO-3 policy, no additional endorsements) based on Austin-metro market conditions: central Austin and Travis County interior areas run roughly $2,800–$3,500. Round Rock and Cedar Park typically land $2,400–$3,000. Kyle and Buda base policies run $2,200–$2,900. Add $800–$2,400 if the property sits in an NFIP flood zone—several Kyle subdivisions near Plum Creek and Onion Creek carry Zone AE designations. Verify flood status at the FEMA Flood Map Service Center before signing, not after. Lakeway and West Austin properties face a different problem: wildfire exposure pushes policies to $3,500–$5,000+, and some carriers have stopped writing new policies in those zip codes altogether.
Two specific flags: Williamson County’s hail corridor is real and priced into local premiums. Round Rock and Georgetown carriers have absorbed significant losses in recent hail seasons. That history lives in your rate whether or not your specific home was ever hit. Pull quotes from at least two independent agents before finalizing your Round Rock decision—not just the builder’s preferred referral. For Kyle and Buda properties, run flood risk and hail exposure as explicit line items before you conclude the tax savings make sense.
Location-Specific Buyer Alerts: Where to Watch Out, Where the Value Is Underrated
Travis County
Austin and AISD neighborhoods carry the full city-plus-county stack. But the 20% Travis County exemption and the metro’s lowest ISD rate make the net bill more competitive than the raw combined rate suggests. On a $450K home in Mueller or East Austin, this table shows an estimated annual bill of $6,200–$6,800—below Round Rock, below Cedar Park, well below Kyle, and with no MUD. Established neighborhoods inside the Austin city limits are also buying into mature utility infrastructure. You’re not funding bond repayment for water and wastewater systems that didn’t exist five years ago. Buyers who dismiss Travis County addresses as automatically unaffordable are working from pre-HB 3 assumptions. The math has changed.
Williamson County
New construction subdivisions in the Cedar Park and Leander growth corridors are almost certainly in an active MUD. Treat it as a given until the required disclosure document explicitly says otherwise—then call the district manager and ask for the current adopted rate, not the maximum authorized rate. These differ, and some sales offices quote the authorized rate. The established sections of Round Rock—Teravista and neighborhoods inside the city limits that predate 2005—often combine a moderate city rate, RRISD’s mid-table ISD levy, and no MUD. That’s the clearest case for suburban savings in this entire comparison, particularly for buyers who aren’t locked into new construction. If you’re shopping for new construction in Williamson County, the MUD question is not optional.
Hays County
Kyle subdivisions built since 2015, particularly around Plum Creek, carry active MUDs. Some run $0.55–$0.75 per $100 AV. Stacked on Kyle’s city rate and Hays CISD’s ISD levy, the total bill on a $450K home can push above $10,000 per year before insurance. That is not a suburban discount.
Buda’s older core neighborhoods near Main Street carry the metro’s lowest city rate in this comparison ($0.3217). They feed the same Hays CISD schools as Kyle. In many cases, MUD bonds have been partially or fully retired. New Buda development in recently platted corridors runs higher—some active MUDs reach $0.75+—but established Buda is genuinely undervalued in this market. The Hays CISD ISD rate is unavoidable anywhere in the county, but Buda minimizes the other lines in the stack more effectively than any other location here. If you’re open to homes built in the 1990s and 2000s, Buda’s existing housing stock offers tax efficiency that new-construction Kyle doesn’t come close to matching.
What to Do With This Information Before You Sign
If a builder rep has quoted you an “estimated effective tax rate” as a single percentage in the last 60 days, ask them to break it down. Get the county rate, the ISD rate, the city rate, and the MUD rate as separate numbers. Then verify each one against the relevant appraisal district’s tax estimator—WCAD, TCAD, or Hays CAD—before the contract deadline.
Run the MUD registry lookup at TCEQ. If your address shows a MUD, call the district’s listed manager and ask for the current adopted rate. Not the maximum authorized rate. They are different numbers.
Pull two independent homeowners insurance quotes from local independent agents before you commit to a suburb. For Kyle and Buda properties near Onion Creek or Plum Creek drainage, request a FEMA flood zone determination on the specific parcel. For any Round Rock or Cedar Park address, ask for hail loss history before accepting the first quote.
If you’re over 62 and moving from an existing Texas property, talk to a CPA or property tax consultant about school tax ceiling portability before you choose a county. The math on that decision can be worth thousands annually. It almost never appears in any buyer’s guide, which is a genuine gap in how this decision gets explained to relocating buyers.
Finally: the Texas appraisal protest deadline is May 15, or 30 days after your appraisal notice, whichever is later. Mark it on your calendar the moment the notice arrives. On new construction, the appraised value frequently comes in higher than expected. The challenge process is straightforward and often produces modest reductions. Miss the window and you’ve lost the opportunity entirely for that year.
The August–September rate adoption window will update several numbers in this table. When final 2026 rates are adopted, this piece will be updated. Bookmark the WCAD, TCAD, and Hays CAD rate pages and check them in October—that’s when the definitive numbers for your first full tax year become available.
The suburban tax discount is real in Round Rock’s established neighborhoods and in Buda’s older core. It’s partially or fully erased by MUD surcharges in most new construction in Cedar Park, Leander, Kyle, and Pflugerville. Once you add insurance and commute costs, the apparent savings in several of these corridors don’t survive contact with a spreadsheet. Run the full number before you sign.
Rates in this article reflect FY2024–25 adopted levies used as proxies for the first full-year 2026 bill. Verify final adopted 2026 rates at TCAD (traviscad.org), WCAD (wcad.org), and Hays CAD (hayscad.net) following September 2025 adoption hearings. This article does not constitute tax or financial advice. Consult a licensed Texas property tax consultant for analysis specific to your parcel.
