Medicare covers the cost of a colonoscopy every 120 months for recipients not at risk of colorectal cancer, or once every 24 months for recipients who have a high risk of the disease, notes Medicare.gov. Medicare covers the cost every 48 months for recipients with previous flexible sigmoidoscopies.
Medicare Part B covers colonoscopies and other types of colorectal cancer screenings, as of 2015, notes Medicare.gov. Other screenings covered include barium enemas, occult blood tests and multitarget stool DNA tests. If the colonoscopy results in removal of a growth, lesion or biopsy during the procedure, the recipient may have a copayment, and the Part B deductible does not apply. Otherwise, there is no copayment for the procedure.