Medicare Part B pays for your outpatient service which includes your doctor visits, physical and speech therapy, supplies, ambulance, as well as lab tests. It does not cover prescription drugs. But, under the new health law, annual physicals and other preventive care are free.
The point is that if you sign up late for Part B, you pay a penalty for each year you delayed enrollment. The penalty is 10 percent of the $1,385 annual premium for each year and there is no cap. For example if you wait five years to sign up, your premium would be 50% higher than someone who signed up on time.
Also remember that Part B has no cap on out-of-pocket costs after Medicare pays its 80 percent. Most people will buy a separate, private, Medicare supplement commonly known as a "Medigap" plan that kicks in where Medicare leaves off.