[Ken H]

“The vast majority of non-pediatric primary care physicians (93 percent) say they accept Medicare—comparable to the share accepting private insurance (94 percent).”

https://www.kff.org/medicare/issue-brief/primary-care-physicians-accepting-medicare-a-snapshot/

The percentage is even higher for medical specialists.

[eastexsteve]

“The vast majority of non-pediatric primary care physicians (93 percent) say they accept Medicare—comparable to the share accepting private insurance (94 percent).”

My primary care doctor will only accept new medicare patients up to a certain point of the year.