You can claim Social Security retirement benefits starting at 62, and many people choose to do that, or to claim shortly after eligibility.

An early claim relative to your full retirement age will shrink your monthly check, but a good number of workers are willing to accept that trade-off because they want to retire early and need Social Security to help them do it.

One thing you should be aware of, though, is that your net income from Social Security checks is most likely going to shrink starting at 65. Here's why that's the case for many seniors, what you should do to plan for it, and why it is not necessarily always a bad thing.

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Here's why your Social Security check is going to shrink at 65

If you have claimed Social Security before age 65, you must be aware that a big change is coming once you hit 65. It stems from the fact that you will become eligible for Medicare for the first time.

Many seniors must sign up for Medicare as soon as they reach eligibility age, because they will face lifetime financial penalties if they don't. Unless you qualify for a Special Enrollment Period or you enroll in a Medicare savings program, you will end up paying an extra 10% penalty for each 12-month period that you could have signed up for Medicare Part B but didn't do so if you didn't have other qualifying coverage.

However, once you sign up, you'll generally owe Medicare Part B premiums.

In 2026, Medicare Part B costs $202.90 per month if you pay the standard premium. Premiums go up most years because of inflation and rising healthcare costs, so the cost will also go up most years.

However, many retirees have Medicare costs taken directly out of their Social Security checks. If you do, once you have Medicare coverage, you can expect that your net Social Security checks will get smaller because you now have your health insurance premium costs automatically withdrawn from the monthly income you collect.

This isn't necessarily a bad thing, as Medicare is an affordable health insurance coverage option many retirees look forward to becoming eligible for. But if you don't realize that you'll have to pay premiums, or that they come right out of Social Security, you may be caught off guard when the payouts you get from Social Security shrink.

Medicare is an important benefit for retirees -- but be sure to understand your options

Medicare Part B is just one of your options for getting coverage through Medicare. You should explore all your coverage options, including Medicare Advantage plans and Medigap coverage, to get the plan that suits your needs.

The first key thing to know, though, is that your net pay from Social Security will likely decline when you switch to Medicare coverage, so you'll need to budget accordingly.