A Personal Health Budget (PHB) is an amount of money to support your health and wellbeing needs, which is planned and agreed upon between you (or someone who represents you) and your local NHS team. It is not new money, but a different way of spending health funding to meet your care needs.
NHS England has produced a short video entitled what are personal health budgets? This describes what they are and how they are helping people get care and support that is right for them. You can also read more on the NHS England website.