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When asked what their biggest regret is when it comes to money, participants in the new CNBC and Acorns Invest in You Savings Survey certainly didn't hold back. From dipping into retirement plan savings to frivolous spending and being too much of an easy touch, here's a look at some of Americans' biggest financial fouls they wish they could do over. The survey, conducted for CNBC by SurveyMonkey in March, polled more than 2,300 adults about various aspects of financial wellness. ---------------

"I didn't start saving early enough in life."

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Woulda, coulda, shoulda. Hindsight may be 20/20, but Aesop's fable of "The Grasshopper and the Ant" has been around for centuries. Most of us are taught the importance of saving from an early age. Alas, forewarned is not always forearmed, and many people approaching retirement look back regretfully — with emptier pockets than they'd like — at their spendthrift 20s, 30s and even 40s or beyond. This was one of the most common regrets supplied by survey respondents. Neglect to start saving early and you'll miss out on the power of compound interest, the ability to cover emergencies without going bankrupt and increased peace of mind. In fact, you'll likely rack up many of the following regrets cited by survey respondents. ----------------

"Gym memberships I don't use and other unnecessary subscriptions."

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Fitness centers are packed each January as people act on their New Year's resolutions and sign up for new gym memberships. But come spring, there's usually plenty of spaces in the gym parking lot. Are you really making good use of that $50 a month membership? Many survey repondents say "no." A similar phenomenon is the plethora of online and subscription TV memberships that people purchase today. Ask yourself: "Do I really need not only a premium cable-TV package but Netflix, Hulu, YouTube Premium and HBO Now subscriptions, as well?" Smartphone app services are another area where people subscribe to what seems like a good deal but which eventually adds up and goes underused, from razor- or perfume-of-the-month clubs to grocery delivery or media outlet memberships. ---------------

"Retail therapy ... with stuff I didn't need!"

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"Spending money on impulsive purchases," "spending all that money on clothes in my 20s," "buying a one-man canoe for $1,000" and even "Amazon Prime." These were all versions of the regret survey respondents reported feeling about impulse purchases that they ended up owing for long after the initial retail high wore off. A lot of those feel-good splurges went on plastic, too — and that debt adds up quickly. The average American had a credit card balance of $4,293 as of this February, according to Experian data, CNBC has reported. Total credit card debt is also at its highest point ever, surpassing $1 trillion this year, the Federal Reserve found. ---------------

"Not eloping."

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The average wedding cost in the U.S. as recently as 2017 was $25,764 — not including the honeymoon — according to nuptial research firm The Wedding Report. Couples, on average, spent between $19,323 and $32,205 but 50% of them actually spent less than $15,000. Still, whether 10 grand or 40, that's a big chunk of change out of anyone's annual bottom line ... and money that could have instead been saved, invested or applied to, say, a down payment on a first home. And don't forget: With some 40% to 50% of U.S. marriages ending in divorce, according to the American Psychological Association, spending tens of thousands of dollars on a party from the get-go might not be the wisest investment. ---------------

"Not divorcing my gambling-addicted spouse sooner."

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"Lending money to a boyfriend." "Helping out people financially who then wouldn't do the same for me." "Co-signing a loan for a friend." Other people can be a big problem when it comes to money, survey responses revealed. Whether it's a compulsive spender or habitual gambler we're financially tied to by law or blood, or a friend who keeps asking for small loans to tide him over till pay day ... cash issues can be a relationship-killer. The fact is, sharing isn't always caring because enabling loved ones who are bad at managing money doesn't really help them — or their benefactors, either — in the long run. ---------------

"Cashing out retirement accounts when I changed jobs."

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"Taking money out of my 401(k) while I was unemployed" and "dipping into my 401(k)" were other typical takes on this kind of regret among survey respondents. It might be tempting to cash out tax-advantaged retirement savings when you part company with a former employer, especially in the case of termination or layoff, when future paychecks might be in doubt. However, by not leaving those funds untouched or rolling them over into a new 401(k) plan or individual retirement account, you'll miss out on future compound interest and earnings on savings. You'll also face taxes, fees and penalties for what amounts to an early distribution. Worse yet, any outstanding loans against your 401(k) balance must be repaid in full within a given period or they'll be considered an early withdrawal. That means you'll be taxed on the outstanding balance, including an early withdrawal penalty if you are not at least 59½ years of age. ---------------

"Maxing out my credit cards in a family emergency."

The importance of having an emergency fund — apart from any illiquid, tax-advantaged retirement savings accounts such as 401(k) plans and IRAs — to tide you over in case tragedy or misfortune strikes cannot be overstressed. Forty percent of people in the U.S. don't have $400 set aside for an emergency, according to the Federal Reserve. CNBC has reported that the average American holds on to just 7.5% of their disposable income. You need to have access to cash so that you don't end up putting emergency expenses on plastic. It's nice to have a high credit-card balance available — but less nice is not being able to pay off that budget-busting balance at the end of the next month. Experts recommend trying to set aside as much as six months' worth of living expenses in a savings account. Sound impossible? A good starting point is aiming to sock away one months' expenses and then build from there. You can put those savings to work for you by opening a high-interest savings account. Bankrate.com has found interest rates as high as 2.4% at online banks. ---------------

"Selling stock too early."

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"I sold Apple stock to pay for college in 2002" and "I took money out of the market in the crash — now I have none." This regret might have cropped up a lot in the survey, in part, because of the Great Recession of 2008 and 2009. More than a few Silent Generation and baby boomer savers with retirement looming just over the horizon panicked at the time and pulled money from a tanking stock market. All the major indexes plummeted by as much or more than 50%, making it the worst market decline since the 1930s ... so who could blame them, right? By not sitting tight and leaving their investments untouched, many of those missed out on the subsequent recovery and boom. Markets had erased those losses by early 2012 and by Aug. 22, 2018, the new bull market — the longest on record — had lasted 3,453 days. The lesson? Historically, on average, markets have always gone up. Leave your stock holdings untouched until it's time to start drawing down your account in retirement ... and then only at the 4% rate usually recommended for retirees, or whatever rate your financial advisor recommends based on your specific circumstances. ---------------

"Racking up so much student loan debt — I should have picked a cheaper college."

"A combined (private/federal, ungrad/grad) student loan balance pushing $100,000." "Getting into $70K student loan debt from my undergraduate degree from a public university." Survey participants had a lot of regrets when it comes to student loan debt. American borrowers collectively owe more than $1.5 trillion in student loans, according to the St. Louis Federal Reserve. Given the ever-increasing cost of higher-education, these loans are hard to avoid. The College Board found that prices tripled at public four-year schools and doubled at public two-year and private non-profit four-years schools from 1988 to 2018. For the 2018-2019 school year, average tuition at the latter type of school was $35,830. However, thanks to scholarships, grants and tax breaks, the average net price paid there was actually $14,610. Big savings to be sure — but 14 grand-plus can still put a big dent in anyone's pocketbook. That's where loans come in. The most recent Survey of Household Economics and Decision-making from the Federal Reserve Board found 42% of college students — and 30% of all U.S. adults — have incurred student loan debt. SHED figures show Americans owe, on average, $20,000 to $25,000 in student loans, with up to $300 per month owed in payments. Seemingly endless debt can add up to a lot of regret, and many Americans are now finding that a college education isn't always the only option — or a forgone conclusion — for those seeking profitable and fulfilling career futures, CNBC has reported. ---------------

"Didn't save for my child's college education so I pulled money from my retirement fund."

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Students themselves are usually not the only ones who end up with college debt. Parents, grandparents and guardians are more often than not on the hook, too, and many threaten their own futures by tapping into their own resources excessively to help cover tuition, room and board and other university expenses. One way new parents and grandparents can avoid the missteps of their predecessors is to open a 529 savings plan. With 529s, CNBC reports, you not only get a tax deduction or credit for contributions (more than 30 states and the District of Columbia offer a direct state tax deduction for your contributions), but earnings grow on a tax-advantaged basis and, when you withdraw the money, it's tax-free if the funds are used for qualified education expenses such as tuition, fees, books and room and board. Total investments in 529s reached a record $328.9 billion in 2018, according to the College Savings Plans Network. ---------------

"Not tithing or giving to charities."

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"That I haven't helped others in poverty." "That I cannot contribute to all the charity requests I receive." Some of the regrets are still weighing on survey respondents' consciences. In business, they say you have to spend money to make money. The same can apply in private life, as well. Donating to worthy causes, whether that be the religious or spiritual organization you belong to or a charitable foundation or cause you deem deserving, can pay its own rewards — and not only by raising your spirits, satisfying moral goals or assuaging nagging guilt for your own good fortune. Historically, there has also been a tax benefit to being charitable. However, the new Tax Cuts and Jobs Act has made it trickier to benefit from beneficence, because it's limited the usefulness of personal deductions — including those for charitable donations. There are workarounds and best practices, however, that can help. ---------------

"Letting bills pile up."

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