GreatSchools provides school performance data (test scores, our GreatSchools 1-10 Rating, and community ratings & reviews). We provide updates of this information to our real estate partners every month. If the data listed on Zillow is different than what is listed on greatschools.org, then Zillow hasn’t uploaded our newest data yet. Always reference greatschools.org for the most current school performance data.
Any school boundary/attendance zone information displayed on Zillow is provided to them by a third-party company called Pitney Bowes. GreatSchools is not involved in that partnership, and we have no way of updating that information.
If a Zillow customer service representative has told you that school boundary data is provided by GreatSchools, they are incorrect. Zillow has formally acknowledged each data provider in their FAQ, here.
You will need to work with Zillow directly to address any issues with Pitney Bowes and/or their school boundary data.