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We report a measurement of the ${B}^{0}\ensuremath{\rightarrow}\ensuremath{\psi}(2S){\ensuremath{\pi}}^{0}$ branching fraction based on the full $\mathrm{\ensuremath{\Upsilon}}(4S)$ data set of $772\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs collected by the Belle detector at the KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider. We obtain $\mathcal{B}({B}^{0}\ensuremath{\rightarrow}\ensuremath{\psi}(2S){\ensuremath{\pi}}^{0})=(1.17\ifmmode\pm\else\textpm\fi{}0.17(\mathrm{stat})\ifmmode\pm\else\textpm\fi{}0.08(\mathrm{syst}))\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$. The result has a significance of 7.2 standard deviations and is the first observation of the …