We're told of the importance of saving for retirement, yet an alarming number of workers aren't listening. Only about 57% of U.S. households aged 35 to 64 are on track to cover 100% of the average costs retirees face, according to the Employee Benefit Research Institute. This means that almost half of today's workers are at risk of running out of money in the future and suffering for it at the worst possible time in life.

Social Security just won't cut it

One factor that prompts many workers to not save for retirement, or not save adequately, is an overreliance on Social Security. So here's a reality check: Though Social Security does help millions of seniors manage their living expenses in retirement, it's extremely difficult, if not downright impossible, for most people to live on those benefits alone.

Senior couple at a laptop with worried expressions on their faces

IMAGE SOURCE: GETTY IMAGES.

In a best-case scenario, Social Security will replace about 40% of the average worker's pre-retirement income. Most seniors, however, need roughly double that amount to pay the bills once they're no longer employed full-time.

Why is this the case? It's simple: Retirement isn't going to alter the bulk of the living expenses you find yourself paying during your working years. Sure, you'll eliminate your commute once you retire, which means you might save a few hundred dollars a month on transportation. But you'll still need a car to get around town, a roof over your head, and food on the table. These major expenses exist regardless of whether you're working.

And let's not forget about healthcare, because that's one cost that actually increases substantially for many seniors in retirement. Though you may come to find that your Medicare premiums are lower than what you paid for health insurance during your working years, there are many commonly utilized services not covered by Medicare, like dental, hearing, and vision, that you'll need to pay for on your own. When you factor in these expenses, plus the copays and deductibles that come with Medicare, you might easily discover that you're spending more on healthcare as a senior -- especially since your health is also more likely to decline when you're older.

And that's why it's so important to build ample savings during your working years. Like it or not, you'll need to replace the bulk of your paycheck once you leave your career, and the sooner you start funding or boosting your nest egg, the greater your chances of retiring in a reasonably comfortable fashion.

Save now, enjoy later

Another factor that inhibits retirement savings is our collective tendency to max out our paychecks on living expenses. The majority of workers today live paycheck to paycheck, which means they eliminate the option to save completely. But if you're willing to cut back on expenses ever so slightly, you can build a decent nest egg without having to part with too much money month after month.

Check out the following table, which shows what sort of impact a $300 monthly contribution to your nest egg might have over time:

If You Start Saving $300 a Month at Age:

Here's What You'll Have by Age 70 (Assumes a 7% Average Annual Return):

35

$497,000

40

$340,000

45

$228,000

50

$147,000

TABLE AND CALCULATIONS BY AUTHOR.

Now clearly, you'll be in a lot better shape if you enter retirement with nearly $500,000, as opposed to just under $150,000. So if your savings window is relatively short, you'll need to set aside more money on a monthly basis to compensate. The point, however, is that it can be done, so if you'd rather avoid a scenario where you find yourself unable to pay the bills as a senior, you'll need to take steps to get your retirement savings on track. That could mean saving some money as opposed to none at all, or saving more than what you're managing at present. But the sooner you make that effort, the fewer financial worries you're apt to face when you're older.

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