A home in Williamson County, TX pays property tax to several entities at once: the county itself, a school district, usually a city, and sometimes a municipal utility or emergency services district. The county’s own 2025 adopted rate is $0.413776 per $100 of assessed value,1Williamson County, TX. Budget and Tax Rate Info but once the other layers stack on, most homeowners face a combined rate somewhere between $1.50 and $2.50 per $100 of taxable value. What you actually owe depends on which entities tax your address, what your home is appraised at, and which exemptions you’ve claimed.
Who Taxes Your Property
The county government is only one line on your bill. The Williamson County Commissioners Court set the 2025 county rate at $0.413776 per $100, covering both the general fund and road and bridge operations.1Williamson County, TX. Budget and Tax Rate Info On a $400,000 home, that layer alone works out to roughly $1,655.
The school district is almost always the biggest line. Round Rock ISD’s 2024 total rate was $0.8931 per $100, split between $0.7101 for maintenance and operations and $0.1830 for debt service.2Round Rock ISD. Taxes Georgetown ISD, Leander ISD, and the county’s other districts each set their own rate every year.
Cities add a third layer. Georgetown’s 2025 voter-approval rate, for example, was $0.353152 per $100.3City of Georgetown. Notice About 2025 Tax Rates Round Rock, Cedar Park, Hutto, and the other municipalities each set independent rates. Newer subdivisions often also sit inside a Municipal Utility District or Emergency Services District that charges its own levy on top. To see the exact entities and rates attached to your address, use the county’s Truth in Taxation portal at williamsonpropertytaxes.org.4Williamson County, TX. Tax Rates
How Your Home Gets Valued
The Williamson Central Appraisal District (WCAD) determines the appraised value of every taxable property as of January 1 each year.5State of Texas. Texas Tax Code 23.01 – Appraisals Generally Market value is what the property would sell for in an arm’s-length transaction between a willing buyer and seller, based on comparable sales, property characteristics, and local market conditions.6Texas Comptroller of Public Accounts. Valuing Property WCAD values thousands of properties at once using mass appraisal, so individual quirks can get missed.
Appraised value is not the same as taxable value. Exemptions and the homestead cap reduce the figure that actually gets multiplied by each entity’s rate. WCAD mails appraisal notices in the spring, and that notice is where you check the number and decide whether to protest.
Exemptions That Lower What You Owe
Texas law offers several exemptions that cut your taxable value before rates apply. Most are not automatic. You have to file with WCAD.
General Residence Homestead
Any homeowner using the property as a primary residence can exempt $140,000 of appraised value from school district taxes. On a $400,000 home, that drops the school-taxable value to $260,000. Counties collecting farm-to-market or flood control taxes must provide an additional $3,000 exemption.7State of Texas. Texas Tax Code 11.13 – Residence Homestead Any taxing unit can also adopt an optional homestead exemption of up to 20 percent of appraised value, with a $5,000 minimum.8Texas Comptroller of Public Accounts. Property Tax Exemptions
Over-65 and Disabled Homeowners
Homeowners who are 65 or older or have a qualifying disability get an extra $60,000 off appraised value for school district taxes, stacked on the general $140,000 exemption.7State of Texas. Texas Tax Code 11.13 – Residence Homestead That shelters $200,000 of value from school taxes.
The more valuable protection is the school district tax ceiling. Once you qualify, the dollar amount of school taxes on your home is frozen at that year’s level and can only rise if you add improvements like a new room or garage.9State of Texas. Texas Tax Code 11.26 Cities and counties can adopt similar freezes, though not all do. Qualifying homeowners also have the option of paying taxes in four equal installments from February through August 1 without penalty or interest.10Texas Comptroller of Public Accounts. Payment Options
Disabled Veterans
Veterans with a VA disability rating of 100 percent, or a determination of individual unemployability, receive a complete property tax exemption on their homestead under Tax Code Section 11.131. Ratings between 10 and 90 percent produce partial exemptions scaled by disability level, from $5,000 off the property’s value at the lowest tier up to $12,000 at the highest. Unmarried surviving spouses can inherit the exemption. Disabled veterans and their surviving spouses also qualify for the quarterly installment option.10Texas Comptroller of Public Accounts. Payment Options
The 10 Percent Homestead Cap
Once you have a homestead exemption, your appraised value for tax purposes cannot rise more than 10 percent per year, plus the value of any new improvements, no matter what the market does.11State of Texas. Texas Tax Code 23.23 – Limitation on Appraised Value of Residence Homestead WCAD still records the full market value on your appraisal notice, but the capped figure is what feeds the tax calculation. In a year when Williamson County values jump 15 or 20 percent, that cap can save thousands. The gap resets only if you stop using the property as your homestead.
How the Bill Is Calculated
The math is simple once you have the inputs. Start with your appraised value (or capped value, if the homestead cap applies), subtract approved exemptions, and you get the taxable value for that entity. Each taxing unit multiplies its own taxable value by its rate per $100. Add the entities together and you have your total bill.
For a $400,000 home in the city of Georgetown and Georgetown ISD with a general homestead exemption:
- School district taxable value: $400,000 minus $140,000 homestead exemption = $260,000
- County and city taxable value: $400,000, assuming no optional local exemption
- County tax: ($400,000 ÷ 100) × $0.413776 ≈ $1,655
- City tax: ($400,000 ÷ 100) × $0.3532 ≈ $1,413
- School district tax: ($260,000 ÷ 100) × the applicable ISD rate
The amounts from every overlapping entity combine on a single tax statement. Check that statement against your appraisal notice and exemption records each year. Errors in exemption coding or recorded square footage happen more often than people expect, and catching them early avoids overpayment.
Protesting Your Appraisal
If WCAD’s value looks too high, you have the right to protest before the county’s Appraisal Review Board (ARB). This is where most homeowners have real leverage over the bill, and no lawyer is required.
What You Can Protest
Texas law lets you challenge the appraised value itself, argue your home is valued unequally compared with similar nearby properties, dispute the denial of an exemption, or correct errors in recorded characteristics like square footage or lot size.12State of Texas. Texas Tax Code 41.41 – Right of Protest The unequal-appraisal argument tends to work well in Williamson County because rapid growth often creates gaps between how similar homes in the same neighborhood are valued.
The May 15 Deadline
File a written protest with the ARB by May 15 or within 30 days of the date WCAD mailed your appraisal notice, whichever is later.13State of Texas. Texas Tax Code 41.44 – Notice of Protest Miss the window and you forfeit the protest for that tax year. Mark the date the moment the notice arrives in April or May.
The Hearing
After filing, you can request an informal conference with a WCAD appraiser to try settling before the ARB sees the case.14Texas Comptroller of Public Accounts. Appraisal Protests and Appeals Many protests end here. Bring comparable sales for similar homes, photos of condition problems, and documentation of anything that drags your value down. If the informal meeting doesn’t resolve it, the case moves to a formal ARB hearing where a panel reviews the evidence and makes a binding decision. You can then appeal to district court or, for properties appraised at $5 million or less, pursue binding arbitration. Property tax consultants work Williamson County on contingency, typically taking around 40 to 50 percent of the tax savings they achieve, so you pay nothing if they don’t move your value.
Payment Deadline and Late Penalties
Tax bills go out in October and are due on receipt. The hard date is January 31. Taxes become delinquent on February 1 of the year following the tax year.15State of Texas. Texas Tax Code 31.02 – Delinquency Date You can pay online at tax.wilcotx.gov, by mail (U.S. Postal Service postmark on or before January 31), or in person at a county tax office.16Williamson County, TX. Payment Options If you have a mortgage with an escrow account, your lender collects taxes monthly and pays the bill on your behalf, but verify the payment actually went out before the deadline.
Missing January 31 triggers penalties that escalate quickly. A delinquent bill incurs a 6 percent penalty in the first month, then 1 percent for each additional month through June. Interest accrues separately at 1 percent per month from the delinquency date.17State of Texas. Texas Tax Code 33.01 – Penalties and Interest
July 1 is the cliff. Any taxes still delinquent on that date jump to a flat 12 percent penalty regardless of when they went overdue. If the taxing unit has contracted with a collection attorney, an additional penalty of up to 20 percent can be added to cover collection costs.18State of Texas. Texas Tax Code 33.07 A $5,000 bill left unpaid until July 1 could carry roughly $600 in penalties, $300 in interest, and up to $1,000 in collection fees, pushing the total near $6,900. Taxes left unpaid long enough become a lien on the property, and the taxing units can pursue judicial foreclosure and a tax sale to recover what’s owed.