78665 Property Tax Rate

Property owners in ZIP code 78665 (Round Rock, Texas) pay a median of $7,554/year in property taxes on homes valued at $438,700. This translates to an effective tax rate of 1.72%, which is 27% above the Texas state average of 1.35%.

The monthly property tax burden for a median-valued home in 78665 is approximately $630, which factors into escrow payments on mortgages. This ZIP code is located within Williamson County. This is $4,423 more than the Texas average of $3,131/year.

Compared to similar ZIP codes in Texas, 78665 has higher property taxes. ZIP codes with similar effective rates include 76140 (1.72%) and 78044 (1.72%).

In Round Rock, property taxes represent approximately 6.4% of the median household income of $117,240, providing context for the relative tax burden on homeowners in this area.

Texas caps annual appraisal increases at 10% for homestead properties, but this cap only applies once you file — submit your Homestead Exemption application to the Williamson County Appraisal District by April 30 of the year following purchase. The exemption removes a portion of assessed value from school and county taxes, typically saving $800–$1,500/year even on a median $370,400 home in this fast-growing county. File your exemption with the Williamson County Assessor immediately after closing and request confirmation of your homestead cap status, as Williamson County appraisals tend to increase rapidly.