SAN DIEGO — The annual open enrollment period for Medicare is set to begin over the weekend, allowing millions of seniors to explore their insurance options.

Open enrollment runs from Sunday, Oct. 15 to Thursday, Dec. 7. It is one of the select time periods that Medicare recipients are able to make coverage changes to their plan.

People enrolled in Medicare will be able to “shop around” during the window, allowing them to choose between the traditional plan or the privately-run Medicare Advantage plans in their area. They will also be able to join or make changes to their Medicare drug plan.

Changes to coverage made over the next few weeks will go into effect on Jan. 1, 2024, according to Medicare officials.

Medicare is the federal health insurance program that is available for those ages 65 and older, as well as some younger people with disabilities. In California, more than 6.6 million residents — about 17% of the state’s population — is on Medicare.

This year, the average beneficiary can choose from 43 different Medicare Advantage plans, including HMOs and PPOs, across nine different insurance companies. According to the research non-profit KFF, the offerings represent the highest number of private plans available to beneficiaries in at least last decade.

Medicare Advantage plans often have prescription drug coverage, as well as extra benefits like dental and vision coverage that is not covered under the traditional plan.

Some Advantage enrollees may be charged a separate monthly premium in addition to the “Part B” outpatient monthly premium. In 2023, the average enrollment premium for these plans was $15 per month, according to KFF.

However, the nonprofit added that seven in 10 beneficiaries were not charged an extra premium. Medicare Advantage plans are generally prohibited from charging more than traditional Medicare.

Earlier this month, the Centers for Medicare and Medicaid Services announced that monthly premiums for “Part A” in-patient coverage and “Part B” outpatient coverage will go up starting next year by about $9.80, or 6%.

Medicare officials encourage recipients who are looking to explore changing plans during this time to review the materials their plans send them, including the “their options during this time should “Evidence of Coverage” (EOC) and “Annual Notice of Change” (ANOC).

Recipients can also call 1-800-MEDICARE or visit to review their options, as well as make adjustments to their plans.

These materials will help people understand what their current plans will look like for the next year. People should pay special attention to how their regular doctors or medications are covered, according to experts.

If they’re satisfied with their current plan and it will meet their needs for the next year, there’s no need to do anything, officials added.

After this open enrollment period closes, another window to make changes will start on Jan. 1, 2024 and run until March 31, 2024.