  We extend previous analyses of the supersymmetric loop correction to the
charged Higgs couplings to include the coupling $H^{\pm}\chi^{\mp}\chi^0$. The
analysis completes the previous analyses where similar corrections were
computed for $H^+\bar t b$ ($H^-t\bar b$), and for $H^+\tau^- \bar\nu_{\tau}$
($H^- \tau^+ \nu_{\tau}$) couplings within the minimal supersymmetric standard
model. The effective one loop Lagrangian is then applied to the computation of
the charged Higgs decays. The sizes of the supersymmetric loop correction on
branching ratios of the charged Higgs $H^+(H^-)$ into the decay modes $t\bar b$
($\bar t b$), $\bar\tau\nu_{\tau}$ ($\tau \bar \nu_{\tau}$), and
$\chi_i^+\chi_j^0(\chi_i^-\chi_j^0)$ (i=1,2; j=1-4) are investigated and the
supersymmetric loop correction is found to be significant, i.e., in the range
20-30% in significant regions of the parameter space. The loop correction to
the decay mode $\chi_1^{\pm}\chi_2^0$ is examined in specific detail as this
decay mode leads to a trileptonic signal. The effects of CP phases on the
branching ratio are also investigated. A brief discussion of the implications
of the analysis for collders is given.
