  In this paper, we obtained the three-dimensional Pauli equation for a
spin-1/2 particle in the presence of an electromagnetic field in noncommutative
phase-space, as well the corresponding deformed continuity equation, where the
cases of a constant and non-constant magnetic field are considered. Due to the
absence of the current magnetization term in the deformed continuity equation
as expected, we had to extract it from the noncommutative Pauli equation itself
without modifying the continuity equation. It is shown that the non-constant
magnetic field lifts the order of the noncommutativity parameter in both the
Pauli equation and the corresponding continuity equation. However, we
successfully examined the effect of the noncommutativity on the current density
and the magnetization current. By using a classical treatment, we derived the
semi-classical noncommutative partition function of the three-dimensional Pauli
system of the one-particle and N-particle systems. Then, we employed it for
calculating the corresponding Helmholtz free energy followed by the
magnetization and the magnetic susceptibility of electrons in both commutative
and noncommutative phase-spaces. Knowing that with both the three-dimensional
Bopp-Shift transformation and the Moyal-Weyl product, we introduced the
phase-space noncommutativity in the problems in question.
