Millions of retirees today collect Social Security, many of whom have come to rely on it as their primary source of income. But for many seniors, depending too heavily on Social Security means struggling to pay the bills.

Though Social Security can certainly help retirees stay afloat financially, it cannot serve as their main income stream, especially given the way costs like healthcare keep climbing. Unfortunately, more than half of today's older workers are at risk of falling into the same trap so many current retirees have landed in. In a new study by the Nationwide Retirement Institute, 55% of adults 50 and over who plan to retire in the next 10 years say that Social Security will be their primary source of retirement income. And that's nothing more than a recipe for disaster.

Older man looking out a window

Image source: Getty Images.

You need more than Social Security

One major Social Security myth that hurts so many seniors is the notion that it's designed to sustain retirees on its own. In reality, Social Security will only replace about 40% of the typical earner's pre-retirement income. If you're a higher earner, that percentage drops.

The problem, however, is that most seniors need roughly 80% of their former earnings once they retire, and the reason for that boils down to the fact that most of their costs don't go down as expected. Take housing, for instance. Many seniors enter retirement having already paid off their mortgages, so by then they're used to not having to make that monthly payment. However, that doesn't negate the need for maintenance, repairs, insurance, and property taxes, all of which are likely to climb, not shrink, over time. The same holds true for food, utilities, clothing, and most of the basic expenses adults of all ages must bear.

Then there are those categories where spending is likely to rise in retirement. Healthcare is a big one -- it'll cost the typical healthy 65-year-old man today an estimated $189,687, while the average woman's tab is projected at $214,565. Furthermore, because retirees have tons of free time on their hands compared to when they were working, they're more likely to increase their leisure spending to occupy themselves.

And Social Security just can't pay for all of that. At present, the average beneficiary collects just over $1,400 a month, which totals less than $17,000 a year. And clearly, that's hardly enough for a comfortable retirement.

Salvaging your golden years

If you've been neglecting your savings because you've been banking on Social Security, consider this your wake-up call to change your ways, effective immediately. Now, the good news is that as long as you have a job, you have an opportunity to build some savings, even if you have none to date.

Currently, workers 50 and older can contribute up to $24,500 a year to a 401(k) and $6,500 a year to an IRA. Max out the former for the next 10 years, and you'll be sitting on $323,000, assuming your investments are able to generate a relatively conservative 6% average annual return during that time. If we apply a 4% annual withdrawal rate from savings during retirement, which has long been the standard, that gives you about $13,000 of yearly income to work with on top of your Social Security benefits.

Another option is to extend your career and hold off on filing for Social Security as long as possible. For each year you delay past full retirement age, your benefits will go up by 8% until you turn 70. This means that if you're looking at a full monthly benefit of $1,400 at age 67, waiting until 70 will boost that figure to $1,736. That's an extra $4,000 of income each year -- for life.

Furthermore, working longer means not needing to tap your nest egg for several extra years, thus stretching the savings you've managed to amass. In other words, if you manage to accumulate $323,000, you're better off using that money over a 17-year period than a 20-year period.

While it's perfectly reasonable to factor Social Security into your long-term financial plan, you can't afford to make the mistake of counting on those benefits to replace your own savings. Doing so essentially means sentencing yourself to years of financial struggles, and frankly, you deserve better.