  We study the muon anomalous magnetic moment in an electroweak model based on
the gauge symmetry $SU(4)_L\otimes U(1)_N$, which has right-handed neutrinos in
its spectrum, and no flavor changing neutral currents at tree level. We discuss
relevant collider and electroweak constraints on the model, and derive the most
stringent upper bounds on the scale of symmetry breaking based on the
corrections to the muon magnetic moment. We conclude that a scale of symmetry
breaking of around 2TeV might explain the muon magnetic moment anomaly. In case
the anomaly is otherwise resolved, using the current and projected sensitive of
g-2 experiments, we rule out scales of symmetry breaking smaller than 3.5TeV
(5.5TeV) at $1\sigma$ level.
