County assessments lag the market and Zillow misses sales, so the gap you're seeing is common; the best source for real comps is a local agent pulling from the MLS. The assessor isn't doing a fresh, granular appraisal of your specific home. They cast a broad data net that often looks back a year or two, so an assessment can rise even when nearby sales feel quiet. And Zillow doesn't show every sale, especially in areas with fewer transactions, so an empty result on one site doesn't mean nothing sold. For actual recent sales: - A local agent can pull true neighborhood comparables straight from the MLS, including sales the public sites miss. - Zillow and Redfin are both decent free tools for a rough look. - An automated valuation model (AVM) run by an agent, or a tracker like Homebot, can estimate your home's value and follow it over time from your address. If your real goal is challenging the tax assessment, gather the closest recent comparable sales and check your county's appeal process and deadline, since a well-supported comp list is what an appeal turns on. Start with an agent's comps, and treat the free tools as a sanity check on top.