Happy New Year! Let's take a look and see how real estate in Williamson County, Texas was for December 2017. Home sales increased a whopping 20% from this time last year. 1,025 residential properties were sold in Williamson County, Texas during December 2017 and there are currently 770 homes under contract waiting to close. The average property spent 75 days on the market and the median price was $290,000. With 1,914 active residential listings in Williamson County, this gives us only a 2.1 month's worth of inventory.