Back to Texas Overview
FIPS: 48491•Rank #22 National•Rank #4 in TX
Williamson County, TX
Forward-Looking Municipal Debt, Assessment Lag & Carrying Cost Audit
Elevated Tax Drift Risk
96% Conf.
Tax Drift Index
63.8/ 100
Elevated Drift Risk
Williamson County Executive Risk Briefing
MSRB EMMA Disclosures & US Census BureauAugust 2026
Williamson County carries a Elevated Tax Drift Score (63.8/100) based on $8,920 in overlapping municipal debt per capita and a +23.5% CAD assessment lag spread. Projected 3-year millage escalation of +0.25% (+25 bps) indicates an estimated +$2,791/yr escrow adjustment on median-priced properties.
Median Home: $460,000Median Income: $99,400Effective Tax: 2.0%
Municipal Debt Per Capita
$8,920
9.0% of Median Income
CAD Valuation Lag
+23.5%
Assessed Value trailing Market HPI
3-Yr Millage Escalation
+25 bps
Effective Rate: 2.0% → 2.3%
Projected Annual Escrow Shock
+$2,791/yr
Estimated on median assessed home
Interactive Property Tax & Escrow Shock Simulator
Model forward-looking ad valorem tax obligations and monthly escrow adjustments for a specific parcel in Williamson County, TX.
$460,000
$0
Current Annual Tax
$9,430
@ 2.05% eff. rate
Year 3 Projected Tax
$12,221
@ 2.30% eff. rate
Net Escrow Increase
+$2,791/yr
+$233/mo mortgage escrow
Projected Shock Attribution Breakdown+25 bps rate shift
1. Muni Bond Debt Service
+9 bps
I&S bond amortization
2. Operating Deficit Drift
+16 bps
M&O budget expansion
3. CAD Valuation Catch-up
+$1,440/yr
+$70,265 assessed base
Overlapping Taxing Jurisdictions & Debt Obligations
Breakdown of autonomous debt issuers assessing ad valorem property taxes on parcels within Williamson County.
| Entity Name | Entity Type | Outstanding Bond Debt | Debt / Student or Cap | Adopted Millage |
|---|---|---|---|---|
| Leander Independent School District | ISD | $2.1B | $49,500 | 1.108% |
5-Year Historical Drift Score & Effective Rate Trajectory
2022
56
1.9% eff.
2023
59
2.0% eff.
2024
61
2.0% eff.
2025
63
2.0% eff.
2026
63.8
2.0% eff.
Statutory Constraint & Legislative Policy
Suburban MUDs and fast-growing school systems (Leander, Round Rock) issue extensive debt for school construction.
Data Provenance & Audit Citations