CJ Karrer
Writer · Reviewed by Richard ChanUpdated Jun 12, 2026
2 min read
Original Medicare Part B covers visits to specialist physicians when they are deemed medically necessary.
Under Original Medicare, you do not need a referral to see a specialist, though you are responsible for the standard 20% coinsurance.
Many Medicare Advantage HMO plans require you to obtain a referral from a primary care physician before consulting a specialist.
A specialist is a healthcare professional who possesses advanced training, knowledge, and expertise in a specific area of medicine. Specialists play a crucial role in diagnosing, treating, and managing complex health conditions that require specialized care beyond the scope of a primary care physician. In this article, we delve into the significance and responsibilities of specialists in delivering expert medical care to patients with specific health needs.
A specialist is a medical doctor (MD) or doctor of osteopathic medicine (DO) who has completed additional years of specialized training, known as a fellowship or residency, in a specific field of medicine. This training enables specialists to focus on a particular branch of healthcare, such as cardiology, oncology, neurology, orthopedics, or dermatology, among others.
Specialists acquire in-depth knowledge and skills related to their chosen medical discipline during their residency or fellowship training. This training involves comprehensive clinical experience and exposure to complex cases that help specialists develop the expertise needed to manage challenging health conditions effectively.
Specialists have several important roles and responsibilities, including:
In many cases, a patient’s primary care physician may refer them to a specialist when they require expert care for a specific medical condition. Referrals are made when a condition is beyond the primary care physician’s expertise, or when a patient’s health needs can be better addressed by a specialist.
Specialists play a vital role in the healthcare system, providing expert medical care and treatment for patients with complex health conditions. With their specialized knowledge and extensive training, specialists are equipped to diagnose and manage intricate medical cases effectively. By collaborating with primary care physicians and other healthcare professionals, specialists ensure that patients receive comprehensive and specialized care tailored to their specific needs, leading to better health outcomes and improved quality of life.