A vertical mount pre-molded type package for use with a MEMS sensor may be formed with a low moisture permeable molding material that surrounds a portion of the leadframes and forms a cavity in which one or multiple dies may be held. The package includes structures to reduce package vibration, reduce die stress, increase vertical mount stability, and improve solder joint reliability. The vertical mount package includes a first leadframe having first leads and molding material substantially surrounding at least a portion of the first leads. The molding material forms a cavity for holding the MEMS sensor and forms a package mounting plane for mounting the package on a base. The cavity has a die mounting plane that is substantially non-parallel to the package mounting plane. The first leads are configured to provide electrical contacts within the cavity and to provide electrical contacts to the base.