Medicare Enrollment in San Antonio: Deadlines, Eligibility & Plan Choices

If you live in San Antonio and you're approaching 65 — or you already qualify through disability — Medicare enrollment can feel like a maze of dates, letters, and acronyms. This guide walks you through the timelines that actually apply in Texas, the plan types sold in Bexar County, and the most common mistakes we see at Good News Insurance Agency.

Who is eligible for Medicare in San Antonio?

You qualify for Medicare in Texas if you are a U.S. citizen or legal resident of at least 5 continuous years and one of the following applies: you are 65 or older, you have received Social Security Disability Insurance for 24 months, you have End-Stage Renal Disease, or you have ALS. San Antonio residents qualify under the exact same federal rules as the rest of Texas — there are no city-specific eligibility differences.

Your Medicare enrollment windows

Initial Enrollment Period (IEP)

Your IEP is a 7-month window: the 3 months before your 65th birthday month, your birthday month, and the 3 months after. Enrolling before your birthday month means coverage starts on the first day of your birthday month. Waiting until later can delay coverage by 1–3 months and may trigger lifetime Part B and Part D late-enrollment penalties.

General Enrollment Period (GEP)

If you miss your IEP and don't qualify for a Special Enrollment Period, you can sign up for Part A and Part B between January 1 and March 31 each year. Coverage starts the month after you enroll.

Annual Enrollment Period (AEP)

From October 15 through December 7, anyone with Medicare can switch between Original Medicare and Medicare Advantage, change Advantage plans, or change Part D drug plans. New coverage starts January 1. This is the busiest season in our San Antonio office.

Medicare Advantage Open Enrollment Period (MA-OEP)

From January 1 to March 31, anyone already enrolled in a Medicare Advantage plan can switch to a different Advantage plan once or drop back to Original Medicare.

Special Enrollment Periods (SEP)

Moving into or out of a plan's service area, losing employer coverage, qualifying for Extra Help, or moving into a skilled nursing facility can each trigger a SEP. SEPs are common in San Antonio for retirees losing group coverage from H-E-B, USAA, the City of San Antonio, or military employers.

The four parts of Medicare in plain English

• Part A — Hospital insurance. Covers inpatient hospital stays, skilled nursing facility care, and some home health. Most people pay $0 premium.
• Part B — Medical insurance. Covers doctor visits, outpatient care, preventive services, and durable medical equipment. Standard 2026 premium is $185/month for most enrollees.
• Part C — Medicare Advantage. Private all-in-one plans that bundle Part A, Part B and usually Part D, often with dental, vision, hearing, and gym benefits.
• Part D — Prescription drug coverage. Sold as a standalone plan with Original Medicare or built into most Advantage plans.

Medicare Advantage vs. Medigap in San Antonio

San Antonio has one of the most competitive Medicare Advantage markets in Texas, with major carriers like Humana, UnitedHealthcare, Aetna, WellCare, and Devoted Health all offering $0-premium plans tied to local networks including Methodist, Baptist Health, and University Health. Medicare Supplement (Medigap) plans cost more in monthly premium but let you see any provider in the U.S. that accepts Medicare. Which one is right for you depends on your doctors, prescriptions, travel habits, and budget.

Common Medicare enrollment mistakes we see in Texas

• Assuming you'll be auto-enrolled. Only people already receiving Social Security at 65 are auto-enrolled — everyone else has to actively sign up.
• Skipping Part D because you don't take prescriptions today. The Part D late-enrollment penalty is permanent and adds up quickly.
• Picking the cheapest premium without checking the provider network. Make sure your San Antonio doctors and preferred hospital system are in-network.
• Forgetting to compare plans every fall. Drug formularies, premiums, and provider networks change every January.

Next step

If you're in San Antonio, Schertz, Boerne, New Braunfels, or anywhere in South Texas and want a licensed broker to walk you through your options, request a free consultation. We work in English and Spanish, in person or by Zoom.