  Extra neutral gauge bosons are a feature of many models of physics beyond the
standard model (BSM) and their discovery could possibly be the first evidence
for new physics. In this Snowmass white paper we compare the discovery reach of
the high energy hadron colliders considered by the Snowmass study for a broad
range of BSM models. It is expected that the LHC should be able to see evidence
for a Z' arising from a large variety of BSM models up to a mass of ~5 TeV when
the LHC reaches its design energy and luminosity, and up to ~6 TeV with the
high luminosity upgrade. Further into the future, the high energy LHC would
substantially extend this reach to ~11 TeV, while the ~100 TeV VHE-LHC could
see evidence for Z' 's up to ~30 TeV.
