The Williamson County Tax Assessor-Collector’s Office In Cedar Park, Texas, will be closed on Monday, July 17, as crews begin construction on an extensive remodel of the tax office. The office will reopen the following day on Tuesday, July 18, with limited staff using temporary space in the same building. The temporary space will be in use until completion of the remodel, estimated for January 2018. Improvements being made include the addition of a drive-thru, expanded lobby seating, more efficient work space and additional workstations for future growth.