A third of Americans plan to retire on Social Security alone, but it may not be enough to get by

• A third of US adults believe Social Security income alone will be enough for retirement.
• A financial expert advises building a 401(k) and HSA to prepare for unexpected expenses.
• A new NerdWallet report shows that the majority of Americans lack sufficient retirement savings.

America's retirees have a lot on their minds.

About a third of US adults believe Social Security alone will provide enough income for them to live comfortably in retirement, but another third said they won't have a retirement account to pull from when they leave the workforce.

That's according to a report published on August 13 by the personal finance firm NerdWallet. In July, analytics company Harris Poll surveyed 2,096 Americans over the age of 18 about their retirement plans on behalf of NerdWallet. Of the respondents, 779 were enrolled in Medicare .

Elizabeth Ayoola, personal finance writer at NerdWallet, said it can be difficult for hopeful retirees to predict how much money they'll need . Many wonder if they're building enough wealth, how long it will last, and if that money is distributed in the right savings accounts.

"Everyone's expenses are going to look different during retirement," she told Business Insider.

NerdWallet's report comes as the US faces a retirement crisis . Millions of older adults don't have the savings or assets necessary to retire from their 9-to-5s or are living from one Social Security check to another. In 2024, the average check is $1,907 , but for many, it isn't enough to get by. What's more, the federal fund could start shrinking by 2030 .

Highly vulnerable to these retirement woes are "peak boomers," the last of the generation who are turning 65 this year — many of whom are caught in the middle of America's switch to a 401(k) system from pensions in the 1980s. Half of adults age 65 and above have an income below $30,000 a year . And, a fifth of Americans over 50 have no retirement savings at all.

BI has heard from boomers who are worried their savings won't last the rest of their lives, and others who struggle each month to afford food, housing, and healthcare. Many worry about becoming financial burdens on their adult children or suffer from loneliness .

"It never hurts to have more than you need for retirement," Ayoola said.

401(k)s can help supplement Social Security income

For the majority of Americans, Social Security is a pillar of their retirement plans. NerdWallet found that about 30% of US adults don't expect to have a savings account by the time they retire — meaning that federal benefits are many people's only option to live on.

Ayoola said it may or may not be realistic to afford basic necessities on a monthly Social Security check, depending on your lifestyle. Some people are comfortable living frugally in retirement , Ayoola said, while others would prefer to travel and have luxury experiences . There are no wrong choices, she said — as long as retirees budget and live within their means.

To best prepare for retirement, Ayoola suggests that people take the time to calculate how much money they will likely spend. She said individuals can most accurately estimate their economic needs by comparing their projected retirement savings and Social Security income with their monthly spending. Cost of living varies widely based on a person's location and lifestyle, she said.

"This can be an intimidating process — some people are scared to see in plain numbers how far behind they are in terms of retirement savings — but it can give you a lot of clarity about what steps you need to take next," she said.

For savings, Ayoola said people can start simple, with "low-hanging fruit." Even adding $50 a month to a 401(k) account throughout a person's career can make a difference, Ayoola said, because the amount grows over time with interest.

Ayoola said it's also important to have a health savings account . About 90% of Americans rely on Medicare in retirement, per NerdWallet. This federal health insurance can help people over 65 pay for prescriptions and basic medical visits, but it might not be enough to cover urgent or long-term care. Ayoola said a health savings account often has tax benefits and can help people avoid draining their retirement savings if they have a health emergency.

To be sure, not all retirees struggle to build retirement savings. Some have strong corporate 401(k) matches or a robust investment portfolio that makes them less reliant on Social Security income.

Ayoola, however, said people can experience financial curveballs —changes in health, increases in expenses, or outliving their savings. It's best to be prepared, even if that means saving a small amount of money over time.

"Although investing and saving for retirement may seem intimidating, it's really about putting one foot in front of the other," she said.

Are you living on Social Security or government assistance? Have you experienced stigma or loneliness because of your finances? If you're open to sharing your story, reach out to allisonkelly@businessinsider.com .