When you first become eligible for Medicare — typically at age 65 — you have a 7-month Initial Enrollment Period (IEP) to sign up without facing a late-enrollment penalty. That window opens three months before the month you turn 65, includes your birthday month, and closes three months after. Missing it can mean permanently higher premiums for the rest of your life, so getting the timing right is one of the most important money moves you’ll make as a new retiree.

What exactly is Medicare Open Enrollment, and does it apply to me as a new retiree?

There are actually two different enrollment periods you’ll hear about, and it’s easy to mix them up.

Initial Enrollment Period (IEP) is for people who are new to Medicare — this is your window. Annual Open Enrollment (October 15 – December 7 each year) is for people already on Medicare who want to switch plans. As a new retiree, the IEP is what matters most right now.

If you’re turning 65 and already collecting Social Security, you’ll be enrolled in Medicare Parts A and B automatically. If you haven’t claimed Social Security yet, you need to sign up for Medicare actively through the Social Security Administration’s website or a local office. Don’t assume it happens on its own.

What does Medicare actually cover — and what will it cost me?

Medicare has four main parts. Think of it like building a coverage puzzle:

  • Part A covers hospital stays. Most people pay $0 in premiums if they or their spouse worked and paid Medicare taxes for at least 10 years.
  • Part B covers doctor visits and outpatient care. The standard Part B premium for 2025 is $185.00 per month — deducted automatically from your Social Security check if you’re already receiving benefits.
  • Part C (Medicare Advantage) is an all-in-one private-plan alternative to Original Medicare. Plans often include dental, vision, and drug coverage.
  • Part D covers prescription drugs. You add this to Original Medicare if you don’t choose a Medicare Advantage plan that already includes drug coverage.

Remember: Part B and Part D are not free. And your income can affect how much you pay — more on that in a moment.

How do I avoid Medicare IRMAA surcharges?

IRMAA stands for Income-Related Monthly Adjustment Amount — a fancy term for a surcharge higher earners pay on top of standard Medicare premiums. If your modified adjusted gross income (MAGI) from two years ago exceeded certain thresholds, you’ll pay more. For 2026, Medicare is looking at your 2024 tax return.

In 2025, single filers with MAGI above $106,000 (or married filing jointly above $212,000) began paying IRMAA surcharges. The extra monthly charges can range from roughly $74 to over $443 per person depending on your income bracket.

Here’s the good news: if your income has dropped significantly since retirement — which is common — you can appeal your IRMAA using Form SSA-44. You’ll need to show Medicare that your income is now lower due to a life-changing event like retirement, and they can base your premium on your current income instead.

To avoid future surcharges, consider strategies like drawing from a Roth IRA (those withdrawals don’t count as MAGI), managing your Required Minimum Distributions (RMDs) carefully, or doing Roth conversions in lower-income years before Medicare kicks in.

When should I claim Social Security to maximise my benefit?

This question is closely linked to Medicare enrollment because your Social Security start date affects when you’re auto-enrolled in Medicare and how your premiums are handled.

The short answer: the longer you wait to claim Social Security (up to age 70), the larger your monthly benefit. Benefits grow by roughly 8% for every year you delay past your Full Retirement Age (FRA), which is 67 for anyone born in 1960 or later. Claiming at 62 — the earliest possible age — permanently reduces your benefit by up to 30%.

That said, waiting isn’t always the right answer. Your health, financial needs, and whether you have a spouse to consider all matter. A common rule of thumb: if you’re in good health and can afford to wait, delaying to 70 often delivers the best lifetime income.

One important note: even if you delay Social Security, you should still sign up for Medicare at 65 to avoid the late-enrollment penalty on Part B.

How much of Social Security is taxable?

Many new retirees are surprised to learn that Social Security benefits can be taxable at the federal level. Here’s how it works:

  • If your combined income (adjusted gross income + nontaxable interest + half of your Social Security benefit) is between $25,000 and $34,000 as a single filer, up to 50% of your benefit may be taxable.
  • Above $34,000 for singles (or $44,000 for married filing jointly), up to 85% of your benefit may be taxable.

Note that this is the portion subject to tax, not a tax rate. Your benefits are taxed at your ordinary income tax rate. Planning withdrawals from taxable vs. tax-free accounts strategically can help keep your combined income below these thresholds.

What are the RMD rules for 2025 and 2026?

Required Minimum Distributions (RMDs) are mandatory annual withdrawals the IRS requires you to take from traditional IRAs, 401(k)s, and most other tax-deferred retirement accounts once you reach a certain age.

Under current law (following the SECURE 2.0 Act), the RMD starting age is 73. If you turn 73 in 2026, your first RMD is due by April 1, 2027 — though taking it in 2026 avoids having two RMDs in the same year, which could push you into a higher tax bracket and trigger IRMAA surcharges.

The amount you must withdraw each year is calculated by dividing your account balance (as of December 31 of the prior year) by an IRS life-expectancy factor. Missing an RMD carries a steep penalty — 25% of the amount you should have withdrawn (reduced to 10% if corrected promptly).

For Medicare planning purposes, large RMDs can spike your MAGI and trigger IRMAA two years later. If you’re approaching 73, talk to a financial advisor about whether a Qualified Charitable Distribution (QCD) — donating up to $105,000 directly from your IRA to charity — can satisfy part of your RMD without it counting as taxable income.

Your Medicare enrollment checklist

Before we wrap up, here’s a simple checklist to keep handy:

  • Mark your 7-month Initial Enrollment Period on your calendar
  • Decide between Original Medicare + Medigap/Part D vs. Medicare Advantage
  • Check whether you’ll owe IRMAA based on your income two years ago
  • If your income has dropped, file Form SSA-44 to appeal your surcharge
  • Coordinate your Social Security claiming strategy with your Medicare start date
  • Plan RMD timing to avoid unexpected premium spikes

Medicare decisions have long-lasting financial consequences, but they don’t have to be overwhelming. Take them one step at a time, and when in doubt, consult a Medicare counselor through your state’s SHIP (State Health Insurance Assistance Program) — it’s a free service available to every Medicare-eligible American.

Frequently Asked Questions

When should I claim Social Security to maximise my benefit?

You can claim Social Security as early as 62, but your benefit grows roughly 8% for every year you delay past your Full Retirement Age (67 for those born in 1960 or later), up to age 70. If you’re in good health and can afford to wait, delaying to 70 typically delivers the highest lifetime income. Even if you delay Social Security, sign up for Medicare at 65 to avoid late-enrollment penalties.

How much of Social Security is taxable?

Up to 85% of your Social Security benefit can be subject to federal income tax, depending on your combined income (your AGI plus nontaxable interest plus half your Social Security benefit). Single filers with combined income above $34,000 — and married filers above $44,000 — may have up to 85% of benefits taxed at their ordinary income rate. Strategic withdrawal planning can help keep your income below these thresholds.

What are the RMD rules for 2025 and 2026?

Under the SECURE 2.0 Act, Required Minimum Distributions from traditional IRAs and 401(k)s must begin at age 73. If you turn 73 in 2026, your first RMD is due by April 1, 2027, but taking it in 2026 avoids doubling up RMDs in one year. Missing an RMD triggers a 25% penalty on the amount you should have withdrawn, reduced to 10% if corrected quickly.

How do I avoid Medicare IRMAA surcharges?

IRMAA surcharges apply when your modified adjusted gross income from two years prior exceeds set thresholds — $106,000 for single filers in 2025. You can reduce future surcharges by drawing from Roth accounts (which don’t count as MAGI), managing RMD timing, and making Roth conversions in lower-income years. If your income has already dropped since retirement, file Form SSA-44 with Social Security to appeal your surcharge based on current income.

What is the Medicare Part B premium for 2025?

The standard Medicare Part B premium for 2025 is $185.00 per month, up from $174.70 in 2024. This amount is automatically deducted from your Social Security payment if you’re already receiving benefits. Higher-income beneficiaries pay more due to IRMAA surcharges, which can push the monthly Part B cost to over $628 per person at the highest income tiers.