Stress analysis of plate-end pressure vessels has hither to been confined to linear bending theories of thin shells. However, the deformations caused by the common junction of the plate-end and the cylindrical body are so high that the linear theory is very inadequate in its prediction of the stress distribution in this critical zone. This paper deals with the stress analysis of plate-end pressure vessels based on Reissner's nonlinear theory of axisymmetric deformations of shells of revolution. The governing nonlinear differential equations of the plate-end pressure vessels are solved by the method of multisegment integration. It is shown that the linear bending theory is highly inadequate in its ability to provide the true nature of the stress distribution in the plate-end and the junction, specifically in thin shells and at high loading intensities. The linear theory is found to be consistently conservative in all cases and the conservativeness increases with increasing thinness of the shell and increasing loading.