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Bounding sup-norms of modular forms in terms of the level has been the focus of much recent study. In this work the sup-norm of a half-integral weight cusp form is bounded in terms of the level: we prove that $\left|\right|y^{\kappa /2}{f̃\left|\right|}_{\infty }{\ll }_{\epsilon ,\kappa }{N}^{1/2-1/18+\epsilon }\left|\right|y^{\kappa /2}f̃{\left|\right|}_{L^2}$ for a modular form f̃ of level 4N and weight κ, a half-integer.