We report the development of a new nonlinear optical crystal CsTiOAsO4 (CTA). The relatively large cesium ion leads to a structural instability in the orthorhombic structure, which significantly affects its crystal growth properties. Modification of the crystal growth process, however, allows the growth of large inclusion‐free single crystals measuring up to 30×20×25 mm3. The refractive indices, nonlinear optical coefficients, electro‐optic coefficients, and dielectric properties of these crystals were measured using standard techniques. Compared to KTiOPO4, CTA has a smaller birefringence which makes it particularly suitable for frequency doubling Nd:YAG lasers operating near 1.32 μm. We also report the ferroelectric poling of multidomain CTA crystals and discuss possible extension of this poling process to other KTP isomorphs.