7 Dangerous Assumptions That Can Quickly Kill Your Retirement Savings

Numerous variables go into every retirement projection, making it an inexact science at best. This is why it always pays to allow for some wiggle room when it comes to forecasting your future retirement account balance.

Be Aware: 6 Cash Flow Mistakes Boomers Are Making With Their Retirement Savings

Try This: 7 Luxury SUVs That Will Become Affordable in 2025

Just a few wrong assumptions about your retirement can dramatically affect your results, so it pays to consider a wide range of possible outcomes. Here are some of the most dangerous assumptions about retirement that could kill your savings fast, along with suggestions as to how to avoid falling into that trap.

One of the biggest variables when it comes to outliving your money in retirement is how long you will live. Unfortunately, this is one of the least predictable variables in any retirement plan given a variety of long-term care needs. Any financial advisor would tell you that healthcare is one of the biggest expenses for seniors and needs to be greatly factored into your big-picture budget.

If you build your entire plan around an assumption that you will live an “average” lifespan, you might run out of money if you end up living a long life, or rather, 30 years or more after full retirement age. While you can make some educated guesses about how long you might live based on your family history and your personal lifestyle, always factor in the possibility that you might live much longer.

Find Out: Cutting Out These 9 Expenses Will Save Retirees Over $29,000 a Year

It’s not just how long you will live but also about how healthy you will be. Healthcare and home care needs could greatly diminish your retirement savings faster than you think. According to last year’s Retiree Health Cost Index, here are a few key takeaways:

• The two most common healthcare coverage options chosen by Medicare-eligible retirees are Medicare Advantage Part D (MAPD) and Original Medicare with Medigap plus Part D.

• A healthy 65-year-old male who retired in 2024 with an MAPD plan is projected to spend $128,000 on healthcare in his remaining lifetime.

• A female with the same coverage is projected to spend $147,000 in her remaining lifetime.

• The difference in cost is largely because women on average live longer than men.

• Under Original Medicare with Medigap plus Part D instead, these projections increase to $281,000 for a male and $320,000 for a female, or a combined total of $601,000 for a 65-year-old couple.

• In today’s dollars (assuming a 3% investment return), this reflects that at least $395,000 in savings is needed.

In many cases, expenses decrease for seniors after they retire. However, that’s not an assumption on which to bank your whole retirement.

If you live in a high-cost area or plan to “live it up” in retirement — eating out often and traveling the world — your expenses may actually increase, which can impact any individual retirement account (IRA) negatively. Plan out your intended lifestyle long before you retire so that you build the appropriate expenses into your budget.

Along with anticipated life expectancy, market returns are the most critical component of a long-term retirement projection. If you invest your account in a balanced portfolio and assume you’ll generate a consistent 7% annual return, you might have a problem if markets hit a rough patch.

While market averages may seem fairly smooth over the long run, over the short run, they can be anything but. From the start of 2000 through the end of 2009, for example, the S&P 500 index, which has a long-term average annual return of about 10%, posted a negative return, averaging a loss of -0.97% every year over that “lost decade.”

For the past 50 years, the U.S. has enjoyed relatively low inflation, averaging about 3.2%. In fact, from 2012 through 2020, the annual change in the rate of inflation never broke higher than 2.4%.

However, over the past few years, the CPI has posted annual gains of 4.7%, 8.0%, 4.1% and 3.2%, respectively. While the Fed seemed to have inflation under control at the end of 2024, 2025 is looking like a much different story. You should factor in rising costs to your retirement projections to ensure inflation doesn’t devour all of your savings.

Many retirees plan on working after they formally retire, hoping to both boost their incomes in order to stretch out their 401(k)s and Roth IRAs and keep their minds occupied. However, you may be forced to retire, perhaps even earlier than you anticipate, due to physical limitations.

In that case, your retirement income will be entirely dependent on your savings, supplemented by Social Security or any pension you may have. As working in retirement may not be possible for every senior, view it as a potential way to generate extra expendable income, not as the solution that will fund your entire retirement.

Some workers assume that they’ll receive an inheritance that will take care of their retirement needs, but that’s a dangerous game. If you fall out of favor with your anticipated benefactor — or if they end up spending more of their money than they anticipate — you might be left with a shortfall that will be impossible to make up.

Always build a retirement plan assuming you won’t receive any outside gifts so that you’re prepared for a worst-case scenario. If you do end up the heir to an inheritance, you can use that money to live a better lifestyle, relieve stress that you’ll outlive your money or perhaps even donate it to a charity.

Caitlyn Moorhead contributed to the reporting for this article.

More From GOBankingRates

This article originally appeared on GOBankingRates.com: 7 Dangerous Assumptions That Can Quickly Kill Your Retirement Savings