I assume you want to fly NZ and accrue to UA's MP?

Then these are the NZ mileage-earning booking classes (all at 100% with no minimum):

EC: U,E,O ("Premium Pacific Class")
EC: Y,B,M,H,T,Q,V,W

All other economy classes will not earn MP miles.

BTW, this info is found for all *A carriers in the UA forum on this thread, linked in the FAQ Sticky .