Using Comparable Properties to Protest Your Williamson County Assessment

The most effective way to lower your Williamson County property taxes is by demonstrating that similar homes in your area are appraised at lower values. These similar homes — "comparable properties" or "comps" — form the foundation of nearly every successful property tax protest in Texas.

What Makes a Good Comp in Williamson County?

A comparable property should be similar to yours in the attributes WCAD uses for valuation:

• Size: Within 20-30% of your home's square footage
• Age: Built within 10-15 years of your home
• Location: Same WCAD neighborhood code or subdivision
• Features: Similar garage capacity, pool status, stories, HVAC type

Williamson County's mix of established neighborhoods in Round Rock and Georgetown alongside rapid new construction in Liberty Hill and Leander means the age and subdivision of your comps matter significantly. A 2005 Round Rock home should be compared to similar-era homes, not brand-new construction in Leander.

The $/sqft Metric

The single most important number in a property tax protest is appraised value per square foot. If your property is assessed at $175/sqft but comparable homes in your WCAD neighborhood are assessed at $150/sqft, that's strong evidence of unequal appraisal.

To calculate: divide the total appraised value by the total living area square footage. For example, a home appraised at $425,000 with 2,400 sqft = $177.08/sqft.

Two Types of Evidence

Equity (Unequal Appraisal) — Usually Strongest

Compare your assessed value per square foot to other properties appraised by WCAD. Under Texas Property Tax Code Section 41.43(b), your appraised value should not exceed the median appraised value of comparable properties, appropriately adjusted.

This is typically the stronger argument because you're using WCAD's own data against them. The ARB must rule in your favor unless WCAD proves your value is at or below the comparable median — the burden of proof is on the appraisal district.

Market Value — Recent Sales

Show that comparable homes have recently sold for less than your appraised value. Use sale dates, addresses, and prices from the last 6-12 months. In Williamson County, this is especially useful when a neighborhood's resale market has cooled relative to WCAD's January 1 valuation date.

How Williamson Value Finds Your Comps

Williamson Value automatically analyzes your property against all residential properties in WCAD's appraisal data — approximately 308,000 properties. Our algorithm scores each potential comp on square footage similarity, year built, neighborhood, and features. Higher-scoring comps carry more weight in the analysis.

Building a Winning Case

• Use 3-5 strong comps rather than many weak ones — quality over quantity
• Highlight the median $/sqft of your comps vs. your own $/sqft
• Include both equity and sales evidence when available — they reinforce each other
• In mixed-age neighborhoods along the I-35 corridor, be careful to match build era — WCAD will challenge comps with significantly different construction years
• Williamson Value generates both types of evidence with a match-scored comp list ready for your protest