You can have both private health insurance and a healthcare cash plan simultaneously, as they serve different purposes. A healthcare cash plan involves paying a monthly fee to cover routine medical appointments, like eye tests or dental check-ups. Health insurance, on the other hand, typically covers treatment for conditions that develop after you obtain the coverage. While health insurance is used for private treatment, a healthcare cash plan can be used alongside the NHS, covering expenses like prescriptions, eye tests, and dental appointments, depending on your location.