From market value to taxed value: what comes off in Williamson County? (DRAFT – not published)

In short

• School taxes in the county were charged on about 69% of market value in 2026. That is about $130 billion out of about $187 billion (our math).¹²
• The state school homestead exemption takes off the most: about $23.8 billion, or about 13% of market value (our math).¹²
• Property that pays no tax, and farm-land rules, each take off about $11 to $12 billion (our math).¹²

Numbers marked “our math” are our estimates, not official figures. The notes show the inputs and the steps.

How it works

• Market value is what the appraisal district thinks a property would sell for on Jan. 1.¹
• Taxable value is what is left after exemptions and special rules. Each taxing unit has its own taxable value. This page uses the school district numbers.¹
• Your bill is the tax rate times your taxable value, not your market value. See how your property tax bill works.

What the numbers show

What comes off (2026, school districts in the county)	Amount	Share of market value
State school homestead exemption	$23.8B	13%
Property that pays no tax (the spreadsheet’s “exempt value”)	$12.0B	6%
Farm and ranch land taxed on what it produces	$11.0B	6%
Age 65 or older exemptions	$3.0B	2%
Disabled veterans	$2.1B	1%
Caps on yearly value increases (homes and smaller properties)	$1.7B	1%
New business equipment exemption	$1.0B	1%
Disability exemptions	$0.2B	under 1%

Source: Williamson Central Appraisal District, 2026 certified values by school district. Totals and shares are our math.¹²

• These items add up to about $54.8 billion. Market value minus taxable value is about $57.5 billion. About $2.8 billion is not explained by these columns (our math).²
• The categories do not fully add up. The appraisal district’s spreadsheet lists the columns but does not define them, so we cannot say what the missing $2.8 billion is.² Most of it sits in four school districts: Taylor (about $0.9 billion), Georgetown (about $0.6 billion), Leander and Round Rock (about $0.3 to $0.4 billion each) (our math).³
• The homestead exemption grew the most. In 2016 it took off about $2.7 billion. In 2026 it took off about $23.8 billion. It is now $140,000 per home.⁴ This sheet does not show how much of the growth came from law changes and how much from more homes.¹

The other side

• This is for school taxes only. The county and cities give different exemptions, so their taxable value is different.¹
• An exemption shifts tax, it does not erase it. When one owner’s taxable value falls, the rate may need to be higher to raise the same money. How much the state makes up to school districts is not shown here.
• Farm land is still taxed. It is taxed on what it produces, which is far below what it would sell for. See farm and ranch land valuation.
• Values can change. 2026 values are as certified in July and can change after appeals.

Changes to this page

• Nov. 2, 2026: Rewrote the questions to ask so each is open, neutral and addressed to the public body.
• Nov. 2, 2026: Added a note that shows how we worked out the figures.
• Nov. 2, 2026: We checked every figure against its source. We reworded the other-side points so they stick to what the sources show.

Questions to ask

• How much of the no-tax property belongs to governments, churches and charities, by the appraisal district’s records?
• Where does the state report the school money it sends back for the bigger homestead exemption?

What we still don’t know

• What makes up the $2.8 billion not explained by these columns. The spreadsheet does not define its columns, and we did not find a definition from the appraisal district.
• Why the spreadsheet’s market value ($187.4 billion) is about $2.9 billion more than adding the value types ($184.5 billion, see what the county value is made of). Almost all of that difference is in the Round Rock school district row (about $3.0 billion) (our math).³

Footnotes

1. Williamson Central Appraisal District, “1999 – 2026 Certified Values” spreadsheet, 2026 tab, school district rows (Market, Taxable, HSState, ExemptValue, AgMkt, AgUse, O65State, O65Local, DVTaken, HSCapAdj, CBLCapAdj, HB9, DPState, DPLocal); 2016 tab for HSState. https://www.wcad.org/historical-data/ ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

2. Our math, adding the school-district rows ($ billions). Market 187.383; taxable 129.861; 129.861 ÷ 187.383 = 69%. Homestead 23.834; no-tax property 11.964; farm 11.101 − 0.105 = 10.996; age 65+ 2.898 + 0.079 = 2.977; veterans 2.091; caps 0.839 + 0.910 = 1.749; business equipment 0.981; disability 0.163 + 0.004 = 0.167. Sum 54.759. 187.383 − 129.861 = 57.522; 57.522 − 54.759 = 2.763. 2016 homestead 2.730. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

3. Our math from the same spreadsheet, 2026 tab, row by row. Unexplained market-to-taxable gap (market − taxable − listed deductions), $ millions: Taylor 891.0; Georgetown 581.4; Leander 357.9; Round Rock 343.9; Liberty Hill 250.5; Hutto 169.1; Jarrell 106.4; others under 60. Market minus the sum of value types: Round Rock 2,981.0; Lexington −85.4; Pflugerville 0.7; all others 0.0. The spreadsheet’s “Define” tab lists column names only. ↩ ↩²

4. Texas Tax Code §11.13(b), school homestead exemption, now $140,000. https://statutes.capitol.texas.gov/Docs/TX/htm/TX.11.htm ↩