Researchers claim that 79% of Americans who take this specific action will not exhaust their funds in retirement.

Determining the amount of money needed for retirement can be challenging due to the unpredictability of certain factors, such as lifestyle choices and life expectancy.

Morningstar researchers are refining their predictions on how most Americans will fare in retirement by updating their U.S. retirement outcomes model, which takes into account various factors such as spending, investing, and life expectancy.

According to Morningstar's model, which takes into account the uncertain future of Social Security benefits, 45% of U.S. households may face a shortfall in retirement. This could force many Americans to consider options such as returning to work, taking on debt, or significantly reducing their expenses to make ends meet.

If you're just starting your retirement savings, there are two key strategies you can implement to significantly boost your chances of having enough money to live on in retirement and leave a legacy for your loved ones.

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An individual is contributing to a retirement account for their workplace. According to Morningstar, 79% of Americans who plan to participate in a defined-contribution plan for at least 20 years will have enough funds to cover their retirement expenses.

Delaying retirement until age 70 can reduce the likelihood of falling short in retirement by 17%.

How to increase your chances of fully funding your retirement

According to Jack VanDerhei, director of retirement studies at Morningstar Retirement and one of the study's co-authors, it is evident that people often struggle with saving less and spending more when planning for a sustainable retirement.

The longer you need to make your savings last in retirement, the higher the chances that you will run out of money if you have not saved enough.

In retirement, you can save in a tax-advantaged account and receive a combination of Social Security, pension income (less common now), and periodic withdrawals from your portfolio.

To ensure that your retirement income lasts, it is crucial to maximize your Social Security benefits and accumulate a substantial portfolio for withdrawals.

Here's how to skew the odds in your favor.

Save in a workplace retirement account

Enrolling in a 401(k) at work can increase the likelihood of a successful retirement by automatically diverting money from your paycheck into your investment portfolio, reducing the chance of spending it.

You may receive a matching contribution from your employer, which financial planners refer to as "free money."

Consistently investing for at least two decades can significantly increase the value of your portfolio through compounding interest.

"If you have access to a plan but don't participate, it's important to highlight that participation is encouraged, says Spencer Look, associate director of retirement studies at Morningstar Retirement and the study's co-author. Just saving something is better than nothing."

Contributing to a workplace retirement account is important, but if you don't have access to one, saving outside of it in an IRA is equally important.

Delay retirement if you can

Delaying retirement as long as possible has a positive "two-pronged effect" on retirement sustainability, according to Look.

To reduce the amount of money you need to have at retirement, you can shorten the time you need your funds to last.

If you want to increase your source of income, you can consider Social Security. For those born after 1960, full benefits are available at age 67. You can claim benefits as early as age 62, but you will receive a reduced amount. On the other hand, if you delay claiming your benefits past full retirement age, the Social Security Administration will increase your benefit by 8% for each year you wait, up to age 70.

Those who retire at 70 have more success in Morningstar's model, and it's wise to work as long as possible, according to Look.

""Retiring at 70 can be dramatic for some people, but it's not possible for everyone. However, working part-time even if you don't have enough savings can be helpful," he says."

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