Despite the surge in availability of online-only bank accounts in recent years, the vast majority of consumers still use branch-based accounts. In fact, only 6% of Americans have an online-only bank account, according to a new survey from personal-finance website WalletHub, and if you're one of them, you could be missing out more money than you think.

Why do 94% of Americans use branch-based banks?

There are some good reasons to use branch-based banking. In fact, my primary checking account is with Wells Fargo and has been for nearly 20 years. (Technically, I opened it with Wachovia.)

A glass jar full of coins, labeled savings and sitting on a wooden surface outdoors.

Image source: Getty Images.

For one thing, it can be convenient to have a branch nearby, in case you need personal assistance or a banking product that you simply can't get online. For example, you can't open a safe deposit box with an online-only bank. In WalletHub's survey, 50% of the people who don't use an online-only bank account say that they haven't switched because they like going to a branch.

Branch-based banks tend to offer a wider array of products than online-only banks as well, and it can be nice to keep everything in one place. In my case, I like having my personal checking, joint checking, credit card, auto loan, and safe deposit box details on the same screen when I log into Wells Fargo's app.

Some of the other reasons people give for sticking with branch-based banking are a bit more surprising. Twenty-seven percent said they simply don't see the benefit of switching (we'll get to that in the next section), and 14% say they've never heard of online-only bank accounts.

The perks of online-only banking

Banking branches cost a significant amount of money to run. You need to have employees, buy office supplies, and keep up with maintenance on the building, just to name a few.

Online-only banks don't have any of these expenses, so they can afford to pay higher interest rates on deposit products than branch-based banks do. And the difference is substantial -- the average online-only bank account pays a 0.87% APY, more than five times that of the average branch-based account. And some pay even more, as you'll see in a second.

Furthermore, online-only banks have lower fees. The average monthly fee for an online-only account is less than half the fee you'll pay with the average branch-based account.

Check out some of the current deals

There are tons of excellent online-based bank account products on the market, many of which pay above-average interest rates. Just to name a few examples:

  • Marcus by Goldman Sachs' online savings account offers a 1.50% APY with an account minimum of just $1.
  • Synchrony Bank's high-yield savings account pays a 1.45% APY with no minimum balance whatsoever.
  • Bank of Internet USA offers an online-only checking account with a 1.25% APY, unlimited domestic ATM fee reimbursement, and the ability to earn cash-back rewards.

How much of a difference could it make?

Here's why this is important. Let's say I have $10,000 that I plan to use to pay my child's tuition in two years. With that kind of time frame, I'm not going to take the risk of investing the money, so a savings account is the way to go. If I deposit the money in a branch-based savings account and collect the 0.16% national average APY, that translates to $32 in interest.

On the other hand, if I deposit it into an online-only bank account with a 1.50% APY, I'll collect $300 in interest over the two-year period. (Note: Because of compounding, both totals would be slightly higher.)

Now, putting money in an online-only bank account isn't going to make you rich. However, in this case, that's almost $270 you would otherwise not have received, just for leaving your money in a safe place.

To be clear, I'm not saying you should completely give up your branch-based banking relationship. I haven't. I'm just saying that if you have a substantial amount of money in savings, or even checking accounts, it may be smart to consider using an online-only bank account for that purpose.

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