The CMS National Plan and Provider Enumeration System currently lists 170 Ambulatory Care Registered Nurse providers with a primary practice address in Massachusetts, all registered under the Registered Nurse NUCC taxonomy branch. Each clinician on this roster selected Ambulatory Care Registered Nurse as their primary taxonomy at NPI enrollment — a self-reported classification that is updated whenever the provider files a correction with CMS. The count excludes organizations (group practices, hospitals, clinics operate under separate NPIs) and excludes providers who chose a different primary specialty even if they practice Ambulatory Care Registered Nurse part-time.

At 170 enrolled providers, Ambulatory Care Registered Nurse in Massachusetts is a limited-supply market — that matters for search-radius decisions, because patients in Massachusetts outside the largest metros often need to broaden to adjacent cities to find a local Ambulatory Care Registered Nurse clinician. The directory below is paginated 50 providers at a time (4 pages total) and is sorted alphabetically by last name, so scanning for a specific practice usually goes faster than scrolling; on the provider detail page you'll find the full NPPES record including address, phone, credentials, and any published Medicare Part D prescribing activity for 2023.

Before contacting anyone on this list, verify the practice is still at the address shown — NPPES refreshes monthly, but providers who have relocated, retired, or changed employers may not have filed an NPI update yet. Important: PlainDoctor is a directory of publicly available CMS government data covering Ambulatory Care Registered Nurse providers in Massachusetts, not a quality ranking, a board-certification verifier, or medical advice. Always confirm credentials through the NPPES NPI Registry, the Massachusetts medical board, and — where relevant — the ABMS, AOA, or the specialty's primary certifying body before making any clinical decision. Nothing on this page substitutes for a conversation with a licensed clinician.