These common money mistakes could cost you nearly $1,000 a year. Here's how to avoid them.

As Financial Literacy Month wraps up, a new survey highlights a costly truth: Even small money mistakes can add up fast.

The National Financial Educators Council estimates Americans lost close to $1,000 last year because of gaps in financial knowledge. At a time when many households are already stretched thin, experts say those losses can mean the difference between building savings and falling deeper into debt.

"It's tough out there," Vince Shorb, CEO of the National Financial Educators Council, said. "That can make a difference between actually saving money at the end of the year and going into bigger debt."

So where is that money going?

Credit cards at the top of the list

The biggest culprit, according to the NFEC survey findings, is credit card interest.

With interest rates hovering above 20% on many cards, carrying a balance even for a few months can quickly snowball. What may seem manageable at first can turn into hundreds of dollars in extra charges over time.

If you're unable to pay off your balance in full each month, experts say a balance transfer card could provide temporary relief. These cards often offer a 0% introductory interest rate, giving borrowers time to pay down debt without accumulating more interest.

The key: Have a plan to pay it off before the promotional rate ends.

Overdraft fees quietly drain bank accounts

Another expensive mistake? Overdrafts.

Banks bring in billions of dollars each year in overdraft fees, often from people who don't realize their account balance has dipped too low. The Consumer Financial Protection Bureau previously estimated that consumers spend $17 billion on overdraft and non-sufficient funds fees.

There are simple ways to avoid paying those fees:

• Monitor your account regularly so you know when your balance runs low
• Set up low-balance alerts through your bank or credit union
• Link accounts for automatic transfers to cover a shortfall  
• Ask your bank to waive the fee, especially if it's your first or second time

Financial advocates say many banks might also be willing to reverse a charge if a customer acts quickly.

Hidden vehicle costs add up

The survey also found many drivers underestimate how much owning a vehicle really costs.

It's not just the sticker price. Gas, routine maintenance, repairs and interest on auto loans can quietly add thousands of dollars over the life of a car.

When budgeting for a vehicle, experts recommend factoring in long-term costs, not just monthly payments, to avoid financial strain down the road.

Confusing financial terms fuel costly mistakes

A separate report tied low financial literacy to confusion over basic money terms. 

According to search data analyzed by BrokerChooser, Americans most often look up definitions for terms like "equity," "APR," "principal" and "yield."

Not understanding concepts like APR, which reflects the true cost of borrowing, not just the interest rate, can lead consumers to choose more expensive loans without realizing it.

Experts say improving financial literacy doesn't require becoming an expert overnight. Learning a few fundamentals, asking questions and double-checking the fine print can go a long way.

As Shorb puts it, "filling in those gaps and shifting behaviors can make a real difference."

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