Social Security Matters – About Signing Up For Social Security & Medicare Part B At 70

By Russell Gloor, National Social Security Advisor at the AMAC Foundation, the non-profit arm of the Association of Mature American Citizens

Ask Rusty – About Signing up for Social Security and Medicare Part B at 70

Dear Rusty: I just turned 69 years old in August 2024 and am still working full time. I signed up for Medicare Part A but, it is my secondary insurance because I have great health insurance through where I work. My wife is retired and has Medicare Part A but, is on my insurance also, and she is taking Social Security. Our plan is for me to work until August 2026 when I’ll be 71. I’ll file for Social Security when I turn 70, and bank all of it for a year until I retire. That is money we plan to use for travel and fun things. I have three questions: when should I file for my Social Security so it starts in September; when do my wife and I file for Medicare Part B (with a supplement) so it starts in September; and are there negative tax implications to this plan that I haven’t thought of? Signed: Needing Info 

Dear Needing Info: Sounds like you have a great strategy planned for your personal Social Security benefits and your Medicare Part B enrollment for both of you. To your questions: 

If you will be 70 in August 2025, you can apply for Social Security about 3 months prior (e.g., in May 2025). Just be sure to specify that you wish your SS benefits to start effective with the month of your 70th birthday. Signing up a few months early is perfectly okay – you will indicate your desired benefit start date on your application, and that is when SS will start your benefits. Remember, SS pays benefits in the month following the month earned, so your first payment will be received in September 2025 (on the 2nd Wednesday if you were born before the 11th of the month). 

As for Medicare Part B coverage for you and your wife, both of you can enroll in Medicare Part B a couple of months prior to you leaving work, but request that Medicare Part B coverage starts in the month your work coverage ends. In other words, you can enroll in Medicare before you retire from work but request that your Part B coverage starts in the first month your employer coverage ends (to avoid any gap in healthcare coverage). Obviously, you should begin your private supplemental healthcare coverage to coincide with the start of your Medicare Part B coverage.  

Regarding the tax implications, just be aware that a portion of your received Social Security benefits become taxable income if your Modified Adjusted Gross Income (MAGI) as a married couple exceeds certain thresholds. FYI, “MAGI” is your Adjusted Gross Income (AGI) on your tax return, plus 50% of your received SS benefits, plus any non-taxable interest you may have had.

If you file your taxes as “married/jointly” and your MAGI is more than $32,000, then 50% of the SS benefits you receive during the tax year becomes taxable income, or if your MAGI as a married couple is over $44,000 then up to 85% of the SS benefits received during the tax year becomes taxable income (at your normal IRS tax rate).

Income tax on SS benefits occurs when your MAGI is over the thresholds for your tax filing status, so you should plan accordingly. If your MAGI will be consistently over these thresholds after you retire from working, you may choose to have income tax withheld from your SS benefits, which is easy to do by submitting IRS FORM W-4V to your local Social Security office. 

This article is intended for information purposes only and does not represent legal or financial guidance. It presents the opinions and interpretations of the AMAC Foundation’s staff, trained and accredited by the National Social Security Association (NSSA). NSSA and the AMAC Foundation and its staff are not affiliated with or endorsed by the Social Security Administration or any other governmental entity. To submit a question, visit our website (amacfoundation.org/programs/social-security-advisory) or email us at ssadvisor@amacfoundation.org.

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