It's no secret that Social Security is a major income source for many retirees today, but some older Americans are relying too heavily on those benefits. In fact, 48% of households aged 55 and over have no retirement savings or pension outside of Social Security, reports the Senior Citizens League. Nearly half of seniors today risk falling behind on their bills and struggling to make ends meet.

Why Social Security alone won't cut it

The average senior on Social Security today collects $1,523 a month, or $18,276 a year. That's not a lot of money to live on to begin with. When we look at healthcare costs alone, those benefits start to look even weaker.

Older couple at table with food and laptop in front of them looking at document

Image source: Getty Images.

The Senior Citizens League estimates that 66% of today's retirees spend more than $375 a month on medical expenses alone. Meanwhile, 31% spend over $1,000 a month on healthcare. Those in the latter category who rely on Social Security as their sole income source have roughly $500 or less to cover all of their remaining bills outside of healthcare. That's clearly a dire situation to be in.

Don't risk poverty as a senior

If you want to enjoy your senior years without having to constantly pinch pennies and stress about living costs, don't plan to depend on Social Security as your only, or even your primary, source of income. First, those benefits have historically done a poor job of keeping pace with inflation. Secondly, there's a chance future benefits will be cut if Social Security's trust funds run out as projected and lawmakers don't find a way to infuse more cash into the program.

Furthermore, as mentioned earlier, the average senior today collects a little over $18,000 a year, and that's without benefit cuts. If you think that's not enough to live on, then you'll need to make an effort to secure outside income. Your best bet in that regard is to save consistently in an IRA or 401(k) plan. Currently, annual IRA contributions max out at $6,000 for savers under 50 and $7,000 for those 50 and over. Meanwhile, 401(k)s come with much higher annual contribution limits -- $19,500 for savers under 50 and $26,000 for those 50 and older. Even if you can't max out your contributions, saving consistently is a good way to secure a robust income stream for your later years.

Funding a health savings account (HSA) is another good option to look at if you qualify (participation hinges on being enrolled in a high-deductible health insurance plan). Annual HSA contributions currently max out at $3,600 for self-only coverage or $7,200 for family-level coverage, but that assumes you're under the age of 55. If you're 55 or older, you can add $1,000 to whichever limit applies to you.

No matter what income sources you secure outside of Social Security, make sure those benefits aren't your only means of paying the bills during your senior years. If you rely on them too heavily, you could be in for a very stressful retirement.