There is a difference between being licensed and certified. Becoming a certified PMHNP shows employers you are capable of patient care in a psychiatric setting. Licensure determines if you are legally allowed to practice in your state of residence. Employers may require board certification before hiring a PMHNP even if practicing without certification is legally permissible.
Each state has their own requirements for licensure. You will need to find the requirements from your state’s board of nursing.
We strongly recommend getting certified after graduating with your master’s degree. You’ll be in the best position to find a great job and follow your career path in nursing.