A pressure transmitter includes an isolator mounting assembly for isolating process fluid from an interior cavity of the pressure transmitter. The isolator mounting assembly includes an isolator plug for receiving the process fluid line pressure and coupling the line pressure to a sensor cavity formed by a header joined to a distal end of the plug. A ring member is attached to the header and the distal end of the plug to reinforce the joint formed between the isolator plug and the head. In another embodiment, the isolator mounting assembly includes a base and a support having first and second opposed ends. The first end is rigidly bonded to the pressure sensor while an epoxy joint joins the second end of the support to the base.