We present a highly accurate model for end-pumped continuous-wave Ho3+:YAG laser resonators, based on a vectorial beam propagation method (BPM) algorithm. Thermal effects in the laser crystal like thermal lensing and stress birefringence are taken into consideration. The implementation of these effects is based on an iterative method, which updates the temperature and displacement in the crystal at specific roundtrip intervals. An experimental Ho3+:YAG resonator cavity in continuous wave operation is used to validate the model. In particular, a resonator showing higher order modes and beam distortions at higher pump power is set up, which shows a very good agreement between the model and experimental results.