Customer Lists and NPS Surveys can be added to Zendesk Professional and Enterprise plans. The cost is €25/license/month (minimum purchase equal to 10 licenses, so €250)
Why add Customer Lists and NPS?
Segment your customers based on profile or support history. Create exportable lists or test your brand loyalty with Net Promoter Score surveys you can send to your lists right from within Zendesk.
For a deeper dive, check out this one-sheeter about Customer Lists and NPS.